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The Religion of Science Library. 


Vol. I. No. 6 Price, 25c 
Bi-Monthly MAY, 1894. Yearly $1.50 


Entered at the Chicago Post Office as second class mail matter, 





rT ae 


THE PSYCHIC LIFE 


OF 


MICRO-ORGANISMS 


BY 


ALFRED BINET 


CHICAGO 
THE OPEN COURT PUBLISHING COMPANY 
1894 


HT 2 


Rye a3 5 


Hrom the Library of 
Professor Benjamin Breckinridge Warteld 
Beyueathed hy him to - 
the Library of 


Princeton Chenlnogiral Seminary 


QL18S 


THE PSYCHIC LIFE OF MICRO- 
ORGANISMS, 





Bae ORG one Sa UAC u 9 9 oe 


OF 


MICRO-ORGANISMS 


A STUDY IN EXPERIMENTAL PSYCHOLOGY 


BY 


ALFRED BINET 


AUTHORISED TRANSLATION 


CHICAGO 
THE OPEN COURT PUBLISHING COMPANY 


1894. 


‘TRANSLATION COPYRIGHTED BY 
THE OPEN CourT PUBLISHING Co. 


CHICAGO, ILL., 1888. 


PREFACE TO THE AMERICAN EDITION, 





I HAVE endeavored, in the following essay upon Micro-organ- 
isms, to show that psychological phenomena begin among the very 
lowest classes of beings; they are met with in every form of life 
from the simplest cellule to the most complicated organism. It is 
they that are the essential phenomena of life, inherent in all pro 
toplasm. 

We admit, accordingly, the Btencs of a vitalism, that is to 
say, of an aggregate of properties which properly pertain to living 
matter and which are never found in inanimate substances. Among 
these properties of life we classify psychological phenomena. 

Vitalism, it is unnecessary to say, has nothing in common with 
the doctrine upheld by the School of Montpellier. The principle 
here involved has nothing to do with properties and forces that are 
superadded to living matter; it concerns the properties that are in- 
herent in it—the properties that characterize life. 

The modern opponents of vitalism seek to confute the theory 
by attempting to explain all phenomena of life from physico-chem- 
ical forces. They maintain that according as physiology advances 
the tendency is to relegate all phenomena nominally physiological 
into the domain of physics and chemistry; and that it would be 
only a question of time, if as yet they had not succeeded in dem- 
onstrating that every vital process is founded upon mechanical 
phenomena. 

In a recent treatise upon ‘‘ Vitalism and Mechanism,’* M. 
Bunge, professor of physiology at Basel, has shown that the his- 
tory of physiology disproves these hypotheses. The more closely 


*G. Bunge, Vztalismmus und Mechanismus, Ein Vortrag, 1886. 


Iv. PREPACE: 


the phenomena of life are scrutinized, the more carefully they are 
studied in their various aspects, the more certain does the conclu- 
sion become that the processes attributed to physico-chemical forces 
in reality obey much more complicated laws. To illustrate, it was 
at one time conceded that the phenomena of resorption and nutri- 
tion were explainable by diffusion and endosmosis; Dutrochet, 
upon his discovery of endosmosis, imagined even that he had dis- 
covered the principle of life. At the present time we know that the 
walls of the intestines do not Sin any wise act like the inanimate 
membrane used in experiments in endosmosis. They are covered 
with epithelial cells, each of which is an organism endowed with a 
complex of properties. The protoplasm of these cells lays hold of 
food by an act of prehension, exactly as the ciliate Infusoria and 
other unicellular organisms do, that lead an independent life. In 
the intestines of cold-blooded animals the cells emit prolongations 
wnich seize the minute drops of fatty matter and, carrying them 
into the protoplasm of the cell, convey them thence into the chyli- 
factive ducts. There is still another mode of absorption of fatty 
matters, met with among cold-blooded as well as warm-blooded 
animals: the lymphatic cells pass out from the adenoid tissue which 
contains them, so that upon arriving at the surface of the intestines 
they seize the particles of fatty matter there present and, laden 
with their prey, make their way back to the lymphatics. 

Accordingly, the faculty of seizing food and of exercising a 
choice among foods of different kinds—a property essentially psy- 
chological—appertains to the anatomical elements of the tissues, 
just as it does to all unicellular beings, in the manner shown in our 
treatise. It is plainly impossible to explain these facts by the in- 
troduction of physico-chemical forces. They are the essential phe- 
nomena of life and are the exclusive appurtenance of living pro- 
toplasm. 

If the existence of psychological phenomena in lower organ- 
isms is denied, it will be necessary to assume that these phenom- 


ena can be superadded in the course of evolution, in proportion as 


: PREFACE. Vv 


an organism grows more perfect and complex. Nothing could be 
more inconsistent with the teachings of general physiology, which 
shows us that all vital phenomena are previously present in non- 
differentiated cells. 

Furthermore, it is interesting to note to what conclusion the 
admission would lead—as Romanes apparently does admit—that 
psychological properties are wanting in lower-class beings and that 
they enter at different stages of zodlogical development. Romanes 
has minutely particularized on a large chart the development of the 
intellectual powers, in quite an arbitrary manner. According to 
his scheme, only protoplasmic movements, and the property of 
excitability are present in lower-class organisms. Memory begins 
first with the echinoderms; the primary instincts with the larve of 
insects and the Annelids; the secondary instincts, with insects and 
spiders; reason, finally, commences with the higher Crustaceans. 

I do not hesitate to say that all this laborious classification is 
artificial in the extreme, and perfectly anomalous. 

All writers that have devoted themselves, with any pretension 
to special investigation, to the study of unicellular organisms, have 
attributed to these beings most of the psychological properties 
which M. Romanes reserves for this or that higher-class animal. 
This is the opinion of Gruber, of Verworn, of Mebius, of Balbiani, 
and of many other naturalists. Moebius recognizes that psycho- 
logical life begins with living protoplasm, and he considers it to be 
the highest aim of zodlogy to demonstrate the psychical unity of all 
animals. 

We could, if it were necessary, take every single one of the 
psychical faculties which M. Romanes reserves for animals more 
or less advanced on the zodlogical scale, and show that the greater 
part of these faculties belonged equally to Micro-organisms. But 
we must not unnecessarily extend the discussions of this introduc- 
tion. We shall accordingly limit ourselves to few illustrations. 

M. Romanes, in his zodlogical scale, assigns the first manifes- 


tations of surprise and fear to the larve of insects and to the An- 


VI PREFACE. 


nelids. We may reply upon this point, that there is not a single 
ciliate Infusory that cannot be frightened, and that does not mani- 
fest its fear by a rapid flight through the liquid of the preparation. 

If a drop of acetic acid be introduced beneath the glass-slide, in 
a preparation containing quantities of Infusoria, the latter will at 
once be seen to flee from all directions like a flock of frightened 
sheep. 

Memory, according to M. Romanes, first begins with the 
Echinoderms. Now, Mcebius, upon the occasion of a treatise upon 
the Folliculina ampulla,* a ciliated Infusory presenting complicated 
and interesting movements, properly remarks that every time an 
animal repeats the same action under influence of the same excita- 
tions, that fact proves that the animal is possessed of memory. In 
fact, memory is one of the most elementary of psychological facts. 

Lastly, the primary instincts, according to M. Romanes, begin 
first with the larvz of insects and with Annelids. We give, in con- 
tradiction of this statement, the recent observations of Verworn, +t 
which reveal the existence of curious instincts among the Rhizopods. 
The Diflugia urceolata, which inhabits a shell formed of particles 
of sand, emits long pseudopodia which search at the bottom of the 
water for the materials necessary to construct a new case for the 
filial organism to which it gives birth by division. *The 
pseudopod, after having touched a particle of sand, contracts, and 
the grain of sand, adhering to the pseudopod, is seen to pass into 
the body of the animal.. Verworn, instead of grains of sand, 
placed small fragments of colored glass about the animal; some 
time afterwards, he noticed a heap of these fragments on the bot- 
tom of the shell. He then saw a bunch of protoplasm issue from 
the shell, representing the new Diffugia produced by division. 
Thereupon, the materials collected by the mother-organism—the 
fragments of colored glass—came forth from the shell and envel- 


oped the body of the new individual in a sheath similar to that en- 


* Moebius, Das Flaschenthierchen, Folliculina ampulla, 1887. 
t+ Verworn, Zeztschrift fiir Wissenschaftliche Zoologie, Bd. 46. H. 4. 1888. 


PREFACE. : VII 


casing the mother. These fragments of glass, loosely interjoined 
at first, were now cemented together by a substance secreted by 
the body of the animal. 

Two facts are to be remarked in this observation: first, the act 
whereby the Difugia collects the materials for providing the young 
individual with acase, is an act of preadaptation to an end not 
present, but remote; this act, therefore, has all the marks of an 
instinct. Further, the instinct of the Diffugia exhibits great pre- 
cision; for the Difiugia not only knows how to distinguish, at the 
bottom of the water, the materials available for its purpose, but it 
takes only the quantity of material necessary to enable the young 
individual to acquire a well-built case; there is never an excess. 

It is interesting to note that the Difflugia does not act differ- 
ently from animals possessing more highly complicated organiza- 
tions and endowed with differentiated nervous systems, as for in- 
stance, the larvze of Phryganids which form their sheaths from 
shells, grains of sand, or minute slivers. 

We shall not regard it as strange, perhaps, to find so complete 
a psychology in the history of lower organisms, when we call to 
mind that, agreeably to the ideas of evolution now accepted, a higher 
animal is nothing morethana colony of protozoans. Every one of 
the cells composing such an animal, has retained its primitive proper- 
ties, giving them a higher degree of perfection by division of labor 
_and by selection. The epithelial cells that secrete the nails and the 
hair are organisms perfected with reference to the secretion of 
protective parts. Similarly, the cells of the brain are organisms 


that have been perfected with reference to psychical attributes. 
€ 


Paris, November 20, 1888. 


ALFRED BINET. 





TABLE OF CONTENTS. 


INTRODUCTORY. 


A branch of Comparative Psychology little known.—Defini- 
tion of Micro-organisms. — Their classification.— Main 
groups of animal Micro-organisms.—Complexity of their 
life of relation.—The Micro-organism not simply an irrita- 
tablet cellular Hin ys. akigy bala eek istee «onl peigiae haat ae 


THE MOTORY ORGANS AND THE ORGANS OF SENSE. 


MOTORY ORGANS. 


Motility.—The pseudopod.— Opinion of M. Rouget relative 
to the formation of pseudopods.—The vibratile cilia.— 
Their morphological significance.—Observations of Engel- 
mann.—The movements of the vibratile cilia are subject 
to the will of the animal.—Observations of M. Balbiani 
upon the Didinium nasutum.—Experiments of Rossbach. 
—The flagellum.— Diversity of its movements.—Observa- 
tion of Biitschli upon the flagellum of the Glenodinium 
cinctum.—Metabolic infusoria.—The granulous bands and 
bright filaments.—The contractile vesicle.—The move- 
ments of Bacteria and Gregarine&... ei... ied. cede ence 


THE NERVOUS SYSTEM. 


Absence of a central nervous system in single-celled organ- 
isms.—Hypothesis of a diffused nervous system.—Obser- 


vation of Gruber upon the Stentor in process of division. 


THE ORGANS OF SENSE. 


Organs of touch.—Organs of sight.—Ocular spot in Flag- 
ellates.—Ocular spot of vegetable zodspores.—Experi- 
ments of Klebs upon the structure of these spots.—The 


Pages 


4-20 


20-22 


CONTENTS. ? IX 


Pages 
hematochrome is not without analogy to the chlorophyl 


pigment.—Opinion of naturalists upon the physiological 
function of the so-called ocular spots.—Observation of 
M. Pouchet upon the eye of the Glenodinium polyphemus. 
— This eye is composed of a pigmentary mass and of a 
refringent body.—Observations of M. Kiinstler upon the 
eye of /Phacus.—Observation of Claparéde and Lach- 
mann.—Observation of Lieberkiihn.—Sensitiveness of the 
Euglena to light.—Experiments of Engelmann.—The vesi- 
cles of Miiller in the Loxodes rostrum... ...cc cece eee ees 22-31 


ads 


NUTRITION. 


Psychical phenomena connected with respiration.—Search 
for oxygen by the bacteria of putrefied matter.--Observa- 
ROMO MEETS ATI oe 4. ghia eee spake et 5S ee cierto wie 31-34 


BL 


THE PSYCHOLOGY OF NUTRITION. 


Psychical phenomena connected with nutrition.—Vegetable, 
or holophytic, nutrition.—-The chromatophores. -—Structure 
ot the chromatophores.—Coincidence between the presence 
of an eye and that of chlorophyl pigment.—Comparison 
between the Luglena and the Peranema.—Nutrition by 
endosmosis, or saprophytic.—Animal nutrition, choice of 
nutriment.—-Prehension of foods by the Ameeba, the Actin- 
ophrys, the Monas, the Acineta.—Opinion of M. Mau- 
pas upon choice by preference.—Capture of food.—The 
vorticel Ciliates.--The Hunter Ciliates. —The Amphileptus. 
—The Didinium nasutum,—Movements of defense and 


DG eee ote ee ats hh cing Fhe ee ta eee velar e wee 34-55 


IV. 


COLONIES OF UNICELLULAR ORGANISMS. 


Colonies of unicellular organisms.—Colonies of single-celled 
organisms have their origin in the segmentations of a 
mother-cellule.— Temporary colonies which are formed 
beneath the cuticle.--The Gonium.—The Eudoryna.--The 


x CONDENS: 


4 Pages 
Volvox.—Difference between a pluricellular organism and 


a colony of unicellular organisms.—Voluntary combina- 
tions: —— Che ‘Bodo cad aus, Qua ic chee ee ne ee eee 55-61 


THE PSYCHOLOGY OF PROTO-ORGANISMS. 


Remarks upon the psychology of Micro-organisms.—Their 
various actions are direct responses to stimuli from the out- 
ward world.—Perception of external bodies.—Choice.— 
Calculation of the positions occupied by external bodies. 
—Movements of Micro-organisms..... Re Betton ee a 61-65 


VI. 


FECUNDATION. 


Fecundation among Infusoria.—Historical.—Psychological 
preliminaries of fecundation-—Observations of M. Bal- 
biani upon the Paramecia, the Spirostomes, and the Sten- 
tors.—Copulation.—Fecundation among the Vorticels.—— 
Observation of Engelmann. —Material phenomena in fec- 
undation.—The rdédle of the nucleus, and the réle of the 
nucleolus.—Description of the phenomena as seen in the 
Chilodon cucullulus (see appendix), the Paramecium bursa- 
via and inthe Paramecium aurelia.—Observation of M. 
Balbiani upon Parameecia, of which the nucleus is overrun 
with parasites... .4 isis Os sip mics Reyne ete smote Te eee 65-75 


VIl. 


FECUNDATION IN HIGHER ANIMALS AND PLANTS. 


Fecundation in higher animals and plants.—The spermato- 
zoid and the ovule can be compared to Micro-organisms,— 
The elements can live for a certain time independent of 
the animals from which they come.—Their motor organs. 
—The movements of the spermatozoid towards the ovule. 
—Length of road to’ be traveled.—Obstacles to be over- 
come.—-Windings and intricacies of the path.—The sper- 
matozoid of the silk-worm.—Arrival of the spermatozoid in 
contact with the ovule.—QObservation of Fol upon the 
fecundation of the star-fish.--The cone of attraction.— 


CONTENTS. 


Sexual selection operating as between different spermato- 
zoids.—Movements of the female element.—-Vegetable 
fecundation.—Progressive differentiation of the two sex- 
ual elements.—-Sexual reproduction of the £ctocarpus stli- 
culosus, after Berthold.—-Investigations of Pfeffer upon 
the spermatozoids of cryptogams.—Action of certain 
chemical excitants upon these elements.—-Specific charac- 
ter of the excitant.—The threshold of excitation.--Appli- 
ERO LANV OEE S LAWS visio ph om tha a de acelaved VAC Rt zntee gaa owas 


VELL 


THE PHYSIOLOGICAL FUNCTION OF THE 
NUCLEUS. 


Functions attributed to the protoplasm and to the envelop- 
ing membrane.—The nucleus, its histological importance 
proved by the phenomena of caryokinesis.—Balbiani and 
Gruber have, at times, observed Infusoria and Actinophrys 
deprived of nuclear substance.-—Nussbaum's and Gruber’s 
experiments of vivisection upon the Svfentor ceruleus.— 
Fragments provided with nucleus reconstruct themselves. 
—Experiments of Balbiani —Facts observed by Gruber, 
in general, confirmed.—Error of Gruber respecting frag- 
ments without nucleus.—These fragments do not con- 
tinue to live, their plasma undergoes disorganization. 
—Experiments of division. — Experiments made upon 
Infusoria while in conjugation.—The presence of the 
old nucleus in a severed fragment only brings about 
an incomplete regeneration.—The nucleus presides over 
all physiological functions, the totality of which con- 
stitutes life. —The regenerative and reproductive property 
of the plasma is lost before the psychical functions are.— 
Agreement of all these facts with the phenomena ob- 
served as taking place during the spontaneous division of 
ISO OES ATI SIS aris hn a as. Bese Meee oa weak FF we ee Smee 


IX, 


CONCLUSION. 


Statement of M. Richet’s position respecting cellular psy- 
chology ....... Mth Aes hte ite fe eee Rae ale Ts 


XI 


Pages 


7579! 


XII COM LLL £55 
Aes Pages 
Romanes’s conception of the psychic activity of Proto- 
OY PANISTIS secre. SM wa cove wher ea ga aion el hae en eee 105 
Irritability and -cellular_psychology. owes eee ee ee 107-110 


Correspondence between Ch. Richet and Alfred Binet, ap- 
pearing in the Revue Philosophique of February, 1888, re- 
printed from THE OpeN Court of December 27, 1888.110-115 


APPENDIX. 
Additional cuts illustrative of : 

The Conjugation of the Paramecium aurelia............ 1i6 
The Conjugation of the Stentor ceruleus...........0.. 116 
The Copulation of the Stylonichta myttlus.... 0.060.060. 116 
The Conjugation of the Carchesitum polypinum.......... ity 
The Conjugation of the Chilodon cucullulus (with explana-- 

tiong) ssc ee ee srenatehea ona D ee abi e ake es cine eee 118 


Addenda. Notes and References omitted in the text...... I2I 





THE PSYCHIC LIFE OF MICRO-ORGANISMS. 


THE study of microscopic organisms has hitherto 
been somewhat neglected by students of comparative 
psychology. Naturalists who have devoted their at- 
tention to the study of these beings, have collected a 
great number of interesting facts concerning their 
psychic life; but these facts have not yet been critically 
examined and collated; they are scattered in reports 
and publications of all kinds, where the psychologist 
never dreams of looking for them. We shall endeavor 
to make him acquainted with a part of this wealth. 

Under the name Micro-organism are included all 
those beings which by reason of their extreme smallness 
and simplicity of structure represent the lowest stages 
of animal or vegetable life; they constitute the very sim- 
plest forms of living matter, and consist of a single cell. 

Some inhabit fresh and salt waters, serving as food 
for a great many other organisms, or contributing by 
means of their calcareous or silicious skeletons to the 
formation of continents. Others live as parasites in 
the organs of animals and plants, and induce more or 
less serious disorders in the constitutions of the organ- 
isms they have penetrated. Others, again, acting like 
ferments produce important chemical modifications in 
organic matter in the course of decomposition. 

A great number of classifications for the methodical 
distribution of these beings has been proposed; but 
not one of them is altogether satisfactory; and that 


F LILLE SMELL Grane ee 


stands to reason. Ifa natural classification is always 
a complex piece of work in the case of the higher ani- 
mals which differ from each other in important features 
and between which a comparison can be instituted, 
the difficulty attending the classification of simple or- 
ganisms which present only the slightest differentia- 
tions is still more difficult. 

The principal division made is that which divides 
them into animal Micro-organisms or Protozoans and 
vegetable Micro-organisms or Microphytes. 

The line of demarcation between these two king- 
doms is far from being well defined; there are a great 
number of micro-organisms ¢zcerte@ sedis, which bota- 
nists usually place in the vegetable kingdom, but which 
zodlogists prefer to classify as belonging to the ani- 
mal kingdom.* 

We give below a list of the most important groups 
of animal micro-organisms. 


ANIMAL MICRO-ORGANISMS. 


INFUSORIA. | MASTIGOPHORES. SARCODINES. SPOROZOA. 
Ciliates Flagellates. Rhizopods, Gregarinida. 
Suctoria (Suckers) Choanoflagellates. Heliozoa. Coccidia. 

BAe anes Saar tee pen Pee Dinoflagellates. Radiolarians, - Sarcosporidia. 
fea ieee Wee whee Cystoflagellates. web. cbc. aa ye0sporiatae 


Soil PAL hk PATE Re ike NE A a eine Ure Sioned. Mierosponraia 


We propose, now, to study the psychic life of these 
lower organisms, or, to speak in more general terms, 
their life of relation. Itis well known that the expres- 
sion, the life of relation, comprehends essentially two dis- 
tinct ideas: first, the action of the external world felt 
by the organism: or sensibility; secondly, the reac- 
tion of the organism on the external world: or move- 


* The best mark to distinguish the two kingdoms is the chemical nature of 
the enveloping membrane: in the case of vegetable organisms, the enveloping 
membrane is made up of a ternary substance, cellulose; while in animal organ- 
isms it is albuminoid in character. 


OF MICRO-ORGANISMS. 3 


ment. It is customary to apply to the union of these 
two properties the name irritability, which expresses 
the reaction of the micro-organism upon exterior 
forces. It is therefore held, and with reason, that 
every living cell is irritable, that is to say that it pos- 
sesses the property of responding by movements to 
the excitations which it suffers. 

In admitting then that irritability is the founda- 
tion of the life of relation, and consequently also the 
foundation of psychology, we must nevertheless guard 
against comparing the autonomous cell of micro- 
organisms to a simple irritable cell. Although the 
body of these small beings may be equivalent to a 
simple cell, it would be an error to believe that their 

life of relation consists in a motory reaction consequent 
upon exterior irritation. At the close of our investiga- 
tions into the psychology of Proto-organisms we shall 
see that, in these inferior beings which represent the 
simplest forms of life, we find manifestations of an in- 
telligence which greatly transcends the phenomena of 
‘cellular irritability. Thus, even on the very lowest 
rounds of the ladder of life, psychic manifestations are 
very much more complex than is usually believed, and 
the conception of cellular psychology which some very 
recent authors have formed, seems to me a very crude 
analysis of the most delicate of phenomena. 

In the great majority of pluricellular animals, the 
life of relation is exhibited in a nervous system and 
ina muscular system. In Micro-organisms the same 
cannot be said to be the case: the greater part possess 
neither a central nervous system nor organs of sense; 
some even lack organs of locomotion. The functions 
of the life of relation are performed by the entire 
mass of the body: many of the Protista, for example, 


ch THLE PSYCH OAL: 


have not a trace of an anatomically differentiated 
visual organ; it is the entire protoplasm of the ele- 
mentary organism that is excitable by light, as it is 
also by heat or by electricity. In other Micro-organ- 
isms somewhat higher in the scale, a beginning of 
differentiation may be seen to make its appearance, 
giving birth either to some vreau of sense or to some 
organ of locomotion. 

We shall give a general description of these organs. 
The study of this first move in the work of differentia- 
tion is of great interest to comparative anatomy and 
physiology; no less interesting is it to psychology. 
Besides dwelling on these preliminaries of our work, 
we shall have occasion to note new and interesting 


facts, 
rE: 


THE MOTORY ORGANS AND THE ORGANS OF SENSE. 


Motility. From the schedule of the groups of ani- 
mal micro-organisms which we have given, it will 
be seen that they are subdivided into four classes, 
the Infusoria, the Mastigophores, the Sarcodines and 
the Sporozoa.. The distinction between these classes 
depends on the existence and the nature of the motor 
organs. 

The Infusoria comprise the protozoa that move by 
the aid of vibratile cilia distributed in greater or less 
number over their body. 

The second class, the Mastigophores, re 
those animals which move by the aid of flagella, that 
is to say by the help of long filaments. 

The third class, the Sarcodines, comprises those 
animals which move by the aid of pseudopodia; which 
are projections of the substance of their, bodies. 

The fourth class, the Sporozoa, is characterized by 


OF MICRO-ORGANISMS. 5 


the mode of multiplication: they are reproduced by 
spores. In the animals of this group, the special 
motor organs are wanting; these creatures therefore 
generally move very little, or they present only move- 
ments of which the principles are unknown. 

We shall successively describe the pseudopodia, 
the vibratile cilia and the flagellum. 

The Pseudopod. -The formation of pseudopodia 
takes place chiefly in naked cells—in cells lacking an 
enveloping. membrane, in the Sarcodines in general. 
They can easily be studied in the Amwba princeps, a 
microscopic animal which is found in abundance in 
fresh water containing organic matter in a state of 
putrefaction. It has the aspect of a small gelatinous 
mass, irregular, formed of a colorless substance, the 
protoplasm. The chemical nature of protoplasm is 
still very imperfectly understood; it is only known 
that it is the result of a mixture of albuminoid mat- 
ters, with an addition of water and mineral elements. 
In the protoplasm of the amceba exists a small rounded 
_and refracting mass, containing one or two bright cor- 
puscles in its interior; this small mass is called the 
nucleus, and the corpuscles the nucleoli. 

The form of the body of the amceba is rendered 
very irregular by the fact that certain parts of the 
mass lengthen, and form short and rounded protuber- 
ances which are designated by the name of pseudo- 
podia. It is by means of these pseudopodia that the 
animal moves; it emits them in the direction in which 
it is going, then it retracts them, while other parts of 
the mass are in their turn elongated. The whole body 
moves by creeping. The amceba in moving has the 
aspect of a drop of oil moving along. To explain the 
mechanism of this movement, it must be supposed 


6 LAE? ESCH G aL Lae, 


that the extended pseudopod seizes some point of sup- 
port with its free end, then, in contracting, draws the 
entire mass of the body up to this. But it is difficult 
to understand what the cause of the elongation of the 
pseudopodia is. It has been supposed that the pro- 
toplasm is endowed with great elasticity and that the 
elongation is the return of this substance to its primi- 
tive form. That is not the explanation given by M. 
Rouget. The learned professor of the Museum has 
been kind enough to write out the following note for 
us, in which he recapitulates his opinion: 


“Every time that a protoplasmic organism dies, or 
is subjected either to a strong electric excitation, or 
to a relatively high temperature (+ 45° to + 50°),the 
pseudopodia are retracted and re-enter into the mass, 
which assumes a globular form; the same is the case 
in the protoplasm of vegetable cells, the inter-cellular 
reticulum of which breaks in receding, or else the mass 
of protoplasm divides into spherical bodies. These 
states of retraction are the analogues of muscular 
rigidity, and like it represent the condition of maximum 
contraction in the protoplasm—nevertheless the style © 
of the Vorticels (Carchestum) which is a protoplas- 
mic formation, under the same conditions, remains in 
a state of permanent retraction. It follows from this 
that the emission of the pseudopodia, ¢hetr elongation, 
cannot in any case be considered as a direct act of the 
contractility of the protoplasm. 7 


“The production of the pseudopodia, one of the 
most difficult problems, cannot, in my opinion, be ex- 
plained, except in the following manner: All proto- 
plasmic masses, and especially the amceba, consist of 
two parts, an enveloping membrane or ectosare, vis- 


OF MICRO-ORGANISMS. 7 


cous and elastic, and the central liquid contents hold- 
ing granules in suspension. 

“From the time of the apparition of a pseudopod, a 
current of liquid is visible which penetrates into the 
pseudopod and which seems to contribute to its elon- 
gation. It is very evident that the liquid is passive, 
that it penetrates into the pseudopod only because, 
pressed upon from all sides, it finds less resistance 
there. I think that the (in appearance) homogeneous 
_hyaline substance of the pseudopod is also a species 
of hernia of the estosarc, resulting from a diminution 
of the elastic resistance at the point where it appears, 
with an increase of elasticity or of contractility (to me 
two modalities of the same property) in those parts of 
the ectosarc where pseudopodia are not produced. 
When the contractility or the elastic tension of these 
parts diminishes, and returns to its original state 
the pseudopod re-enters into the mass. Add to this 
that, in an amceba of large dimensions, Ameba ferrt- 
cola, it has seemed to me that the most external mem- 
brane of the ectosarc showed striwof a granular ap- 
pearance which may be identical with the strizor con- 
tractile fibrils of the ectosarc of the ciliated infusoria, 
Stentor, Spirostomes, Bursaria, etc.” (May 20, 1887.) 

The pseudopod does not represent a permanent, 
differentiated organ of locomotion; it is produced bya 
simple prolongation of the mass of the body, which 
can take place at any point whatever, and when the 
act of locomotion has been accomplished, this pro- 
longation re-enters into the common mass. without 
leaving any traces of its emission. In other animal 
species, for example the Pefalobus of Lachmann, 
initial traces of differentiation of the pseudopodia 
have been observed; they always form at the same 


8 THE PSV CHIGALLLLE 


point of the body, on a level with the anterior part; 
but, in spite of this constant localization, the motor 
organ has only a transitory existence; it is produced 
at the moment it is needed, and disappears into the 
mass of the body, when the movement has been exe- 
cuted. In the Actinophrys there is a still greater pro- 
gress: the numerous pseudopodia emitted by this ani- 
mal, and which have the form of filaments, are perma- 
nent organs with definite functions. 

The Vtbratile Cilia. The vibratile cilia are short, 
extremely thin, homogeneous filaments which are agi- 
tated by a vibratory movement. These are distinctly 
differentiated organs of locomotion. They have, 
moreover, several functions: firstly, they enable the 
animal to move about in the liquid; secondly, they 
serve it as an organ of prehension; thirdly, they per- 
mit a renewal of the water which furnishes the neces- 
sary air for respiration to the animal; perhaps they 
also serve as organs of touch. 

The vibratile cilia lend to the Infusoria their peculiar 
character and enable them to be distinguished from 
all the other Protozoa. Cilia are also found in’ 
vegetable species when young, and in the larve of 
Coelenterates, of mollusks and of worms. But 
among the Protozoa, it is the Infusoria alone that are 
ciliated. The cilia are distributed in various manners, 
differing according to the species. In the holotricha, 
they are distributed regularly over the whole surface 
of the body, and almost all have the same length; in 
the Heterotricha, they also cover the whole surface of 
the body, but they are unequal in length. To this 
group belong the Szentors which have long cilia in- 
serted around a circular surface, extending almost to 
the mouth. This surface is a rotatory organ, analo- 


OF MICRO-ORGANISMS. 9 


gous to that of the rotifers; it produces eddies in the 
water and thus causes the flow of foreign bodies to the 
mouth: these animals have the- rest of their bodies 
covered with fine cilia. In the Ayfotricha the cilia 
are located on the ventral surface of the body and aid 
in locomotion. In the Peritricha, they form a cir- 
cular or spiral row on the anterior part of the body, 
and lead tothe mouth. This is observed in the Vor- 
ticels, sessile species which have no other cilia than 
those which are used for the prehension of food; the 
rest of the body is bare. 

Much has been said about the morphological signif- 
icance of vibratile cilia; several micrographists have 
held that the cilia are attached to the enveloping mem- 
brane only, and have no connection whatever with the 
protoplasm. That was notably the opinion of Robin; 
itis entirely wrong. ‘The cilia are never simple pro- 
longations of the cuticle; they have their root in the 
protoplasmic substance; they pass through orifices in 
the cuticle, which consequently is pierced by a multi- 
tude of small holes. Engelmann, in recent observa- 
tions, has been able to trace the extremity of the vibra- 
tile cilia into the interior of the protoplasm; he made 
this observation on the marginal cilia of the Stylo- 
nichia; from each of these threads he has seen sep- 
arate a pale fibre, which moves along almost directly 
beneath the cuticle in a direction perpendicular to the 
lateral edge of the body; towards the median line of 
the ventral face the fibres are often laid bare, because 
the body of this Infusory voids its protoplasmic sub- 
stance; there the fibres have the aspect of. tightened 
threads. Engelmann sees in this observation a con- 
firmation of the opinion that the bodies of infusoria 
are formed of one single cell, because, according to 


IO LHE PSV CHLC-LLILE 


other observers, there exist also in vibratile cellules 
filiform striz which seems to be a continuation of the . 
cilia, and which traverse the protoplasm of the cell 
throughout its whole length. 

We might add to this direct observation several 
other facts showing that the vibratile cilia are indeed 
prolongations of the plasm. Under the action of 
re-agents the cilia act like the cellular protoplasm; 
they are coagulated by the acids and dissolved by 
weak alkalies,-while the cuticle offers a greater resis- 
tance to these same agents. 

These vibratile appendices are not without analogy 
with the pseudopodia of naked cells; Dujardin, a 
French naturalist, demonstrated this in 1835, although 
efforts have since been made to bestow the honor of 
this discovery upon the Germans. Dujardin has 
proved that the amceboid movement and the ciliary 
movement are only two manifestations of the con- 
tractile power of protoplasm. In fact, if instead 
of examining a pseudopod with lobed outline hke that 
of the amceba, we observe the slender and flamentous 
pseudopodia of the Foramenifera, we see that the ex- | 
tremity of the filament is agitated by the same vibra- 
tory movement as the vibratile cilium. 

All the transitions from the fine and delicate cilia 
to the large cilia, tapering in form like a stilleto, which 
have been called cirri, have been observed; moreover 
these cirri are formed of agglutinated cilia; by the aid 
of certain re-agents they have been dissociated: 

An observation of a ciliated infusory, the Didinium 
nmasutum (see the illustration further on) made by M. 
Balbiani, shows that the movement of the cirri is not 
an involuntary movement like that of the cilia of the 
vibratile epithelium, with which it has often been 


OF MICRO-ORGANISMS. II 


compared, but that it is completely under the control 
of the will of the animal, like the organs of locomotion 
of animals much higher in point of organization. 


“The Didinium has two rows of equal, and rather 
strong, vibratile cilia, disposed transversely around 
the body, in the form of two belts or crowns. The 
rest of the body of this animal is entirely stripped of 
cilia, but its double vibratory belt suffices to enable it 
to execute the most rapid and most varied evolutions 
in the water. Not only does it swim forwards and 
backwards with perfect ease, but the progression in 
both directions is always accompanied bya rapid rota- 
tory movementof the animal aboutits longitudinal axis, 
similar to that observed in other infusoria that have a 
cylindrical body. The two rows of cilia always act in 
union during the locomotion, and the direction which 
the animal gives to them, determines the direction in 
which it wishes to move. In the movement for- 


Fig. 2.—Didiniunt na- 
sutune (Balbiani). Out- 
line of movement back- 
wards. The cilia are 


Fig. 1.—Didinium na- 
sutum (Balbiani) Fig- 
ure representing move- 
ment forward.The cilia 


Fig. 3.—Didiniunt na- 
sutunt (Balbiani). A 
sketch of rotatory 
movement in one spot. 


are all turned towards 
the front part of the 


body. 


all turned towards the 
back part of the body. 


The cilia of the ante- 
rior belt are directed 
forwards, while those 


of the posterior belt 
are directed backwards 


wards, all the cilia are directed toward the an- 
terior part of the body (fig. 1); when it swims 
backwards, they are reversed (fig. 2). The in- 
fusory thus rapidly makes its way across the field of 
vision by jerks; from time to time it suddenly stops, 
all the time continuing to turn around rapidly on its 


12 TELL PSY CALC eh LICE 


axis on the one spot, during which movement the cili- 
ated belts beat the water in opposite directions, the 
anterior ones being turned forwards, while the posterior 
are turned backwards (fig. 3). The result of this is 
that the effects of these small locomotive apparatuses 
neutralize each other in the same manner as two heli- 
ces acting in opposite directions, and that the animal 
remains stationary, while all the time turning rapidly 
about itself, sometimes horizontally, sometimes verti- 
cally on its conical appendage, just as on a pivot.” 
Certain Infusoria, for example the Condylostoma 
patens, which has been thoroughly studied by M. 
Maupas, possess at the same time the two kinds of 
appendages, the cilia and the cirri. The former, which 
cover the dorsal surface of the animal, are fine, very 
dense and animated by a rapid and unceasing vibra- 
tile movement. The cirri, which cover the ventral 
surface are placed apart; furthermore they do not vi- 
brate rapidly; their movements are slow, and when 
the infusory moves, one can see them move success- 
ively on the plate of glass and support themselves 
there, in the manner of a foot, to make the body ad- 
vance. When the animal stands still, the cirri are ab- 
solutely immobile, while the cilia continue their vibra- 
tile movement. This observation which can equally 
well be made of the Oxytrichid, shows that the vibra- 
tile cilia are the organs of involuntary movement, and | 
that the cirri are more directly subject to the will. 
The fact is demonstrated by the experiments of Ross- 
bach, who observed that, under the influence of the 
falling of the temperature (from + 15 to + 4) or of 
the rising of the temperature (from + 35 to + 40) or 
under the influence of various chemical substances, 
the large cilia, the organs of voluntary movement,are 


OF MICRO-ORGANISMS. 13 


paralysed, while the fine and delicate cilia continue 
their movements, which do not seem to be under the 
influence of the will. These movements alone cause 
the whole body to rotate until the vibratile cilia are 
in their turn paralyzed. 

Besides the cilia and the cirri, other appendages 
in the form of membranes are found among the Infu- 
soria, appendages which are attached to the anterior 
part of the body or the peristome; these membranes 
serve the purpose of causing eddies in the water, 
which bring the floating alimentary particles into the 
mouth. They are modifications of the vibratile cilia; 
these membranes like the cirri are formed of aggluti- 
nated cilia. 

The Flagellum. The study of the third organ of lo- 
comotion, the flagellum, brings us to speak of the 
class of Mastigophores and more particularly of the 
group Flagellata. The Flagellates are Protozoa of 
very small size, all in all, very much smaller than the 
ciliated Infusoria. They have no vibratile cilia at all, 
but -they are always equipped with one or more fila- 
mentous appendages which have the form of a long 
lash. This is the flagellum. This lash, like all the 
organs of locomotion hitherto studied, has two func- 
tions: it is at once an organ of locomotion and an 
organ of prehension. The flagellum is most fre- 
quently single or double (see fig. 4, representing the 
Luglenadeses with its single flagellum); sometimes a 
person can count a much larger number of them, four, 
six, eight, ten, and more. As regards the insertion, 
the same variations are met with. Sometimes the 
flagella are very numerous and seem to be planted on 
the same point of the surface of the body, thus forming 
a brush or plume. In other species we find several 


14 THECPSYVCHILCALLLE 


flagella arising in the anterior extremity of the body, 
directed forwards, and also posterior or caudal fila- 
ments which are turned toward the rear. This is 
observed in the genus 77¢chomonas,; the anterior fla- 
gella serve for purposes of locomotion, perhaps also 
for the prehension of food; the posterior flagella, on 
the contrary, are solely organs of loco- 
motion; they resemble a trailing tail 
and perform the functions of a rudder. 

In passing we may point out the 
great morphological resemblance be- 
tween the Flagellata and the sperma- 
tozoa of animals, the antherozoa and 
the zodspores of plants. The organs 
of propulsion in these beings are the 
same. 

The Protozoan with its flagellum 
executes the most varied movements, 
moving first in one direction, then in 
another, and in different planes; some- 
times the animal curves about entirely; 
but most frequently, when he uses it 
as an organ of prehension, he extends 
it its whole length before himself; the 
basilar part remains completely immov- 

Fig. 4. able and rigid, while the free end alone 
Euglenadeses, f F 
+c. = contractile re. CxeCUteS Movements destined to drive 
servoir; o. — eye; # food to the mouth, which is generally 


= disk of the para- — 
mylone; ck. — chro- situated at the base of the flagellum. 


matophores; 7. = nu- 

cleus. ‘Ehrenberg gives to the flagellum the 
name proboscis; its peculiar mobility renders it worthy 
of thisname. The flagellum, like the vibratile cilium, 
is an expansion of the protoplasm through the envel- 


oping membrane. M. Certes has observed a Proto- 





OL MICRO-ORGANISMS. 15 


zoan, the flagellum of which between whiles re-entered 
into the mass of the body, with which it mingled;it 
was replaced by a pseudopod which soon attenuated 
and took the form of a flagellum. 

Bitschli has recently made a very interesting ob- 
servaticn on this organ of locomotion. Under certain 
circumstances, the Peridinia (Dinoflagellates) throw off 
their long flagellum and enter into a state of repose; 
they generate them quite as easily. In the Glenodin- 
zum cinctum, Biitschli has seen the flagellum roll itself 
up first like a cork-screw, and then suddenly detach 
itself from the animal; having become free, it stirs 
about in the water for several minutes before becom- 
ing motionless. ‘This observation enables us to refute 
those naturalists who believe that, the vibratile cilium 
is an appendage of the cuticle, by bringing forward 
the fact that when the cilia with the portion of the cu- 
ticle in which they are inserted are separated from the 
cell, the cilia continue to move; we have just seen 
that the flagellum moves even after it is separated 
from the cuticle; this persistence of movement is 
sufficiently explained by the protoplasmic nature of 
the cilia and of the flagellum. 

From another point of view, the observation of 
Bitschh gives us a curious example of the phe- 
nomena of autotomy, which have recently been studied 
by Frédéricq. 

The pseudopodia, the vibratile cilia, and the flagel- 
lum, constitute the three motor organs that are most 
frequently found in the kingdom of the Protista. 
Among the Infusoria, moreover, particular differentia- 
tions of- the protoplasm have been described, which 
may be compared to the muscular fibres of the higher 
animals. The Vorticellaz are supported by contractile 


16 | ATER PSV CHIC DERE 


peduncles. These are filaments capable of rolling 
themselves up into the form of a cork-screw, when the 
animal is disturbed. Certain Infusoria can modify 
the form of their body by a sudden contraction: they 
have been called metabolic; such are the Stentors, 
the Prorodons, the Spirostomes. In contradistinction, 
those which do not change their form, for example the 
Paramecia, have been called ametabolic. Accord- 
ing to the observations of Lieberkithn, which date 
back to 1857, the metabolic Infusoria have their 
bodies divided into large granulous bands, separated 
by bright filaments. It has been asked which is the 
contractile element: is it the band, or is it the fila- 
ment? Oscar Schmidt, Kélliker, Stein, and Rouget 
think that it is the band which is the contractile ele- 
ment. This opinion is based on the following fact, 
which M. Rouget was the first to observe: at the mo- 
ment at which the animal contracts, the band presents 
transverse striae; this appearance is due to the fact 
that the bands contain in the state of rest small gran- 
ules which, during the contraction of the animal, are 
disposed in transverse series, so as to recall the sax- 
cous elements of Bowman. : 

Lieberktthn, Greef, and Engelmann attribute the 
active part to the bright fibre. Engelmann has based his 
opinion on the fact that he recognized in the filament 
the property of double refraction, which, according to 
him, belongs to all contractile substances, while the 
substance which separates the filaments shows only 
single refraction. 

However that may be, it is one of these two ele- 
ments that possesses the power of contraction, and 
which deserves the name of myophane, which Haeckel 
gave it. It is very remarkable that in the Stentors 


OF MICRO-ORGANISMS. 17 


and the Spirostomes the fibrillous striz are in intimate 
connection with the basilar extremity of the vibratile 
cilia. In the Vorticellz one can clearly see the fibrils 
converge toward the axis of the style, the contractile 
element of which they constitute. 

We shall not leave the study of the motor organs 
without saying a word about the rhythmical movements 
which can be seen in the contractile vesicle of the 
Micro-organisms, vegetable as well as animal. This’ 
vesicle is a small cavity which is dug into the proto- 
plasm, and which alternately increases and diminishes 
its capacity. Scientists byno means agree as to its ex- 
act function; Biitschli and Stein consider it to bea 
secretive apparatus. Its pulsations are very regular. 
Their number is constant in every species. In the 
chilodon cucullulus, a pulsation occurs every two sec- 
onds; in the Crytochium nigricans, every three sec- 
onds; in the Vorticelle, every eight seconds; in the 
_ ELuplotes, every twenty-eight seconds; in the Acitnerza 
wncurvata, every six minutes; Rossbach, whose curi- 
ous experiments with the vibratile cilia and the cirri 
we have already cited, has made analogous experi- 
ments with the contractile vesicles. He observed es- 
pecially that, under the action of alkaloids, the con- 
tractile vesicle ceased pulsating in diastole, and di- 
lated enormously; but poisonous agents do not act 
all at once on the movements of the vesicle; they begin 
by paralyzing the larger cilia, which are under the in- 
fluence of the will. The movements of the vesicle, 
like those of the small cilia, persist for a much longer 
time. M.E.Maupas has seen Paramecia, killed by 
a discharge of trichocysts, become completely immo- 
bile, with their vibratile cilia inert and rigid, 
while the contractile vesicle continued to pulsate 


18 THE PSVCHICRL LIE, 


with the same activity; this activity continued for an 
hour. 

We have now briefly examined the morphology of 
the motor organs of Micro-organisms. 

It is very difficult to determine the physiological 
process of the movements produced by these organs. 
The simplest movements and the ones most easily un- 
derstood, are those by which a cell suddenly and 
strongly irritated withdraws its prolongations and as- 
sumes a spherical form; this change of form can be 
explained by a quick condensation of the protoplasm, 
which becomes the seat of a phenomenon similar to 
that of a contracting muscle. The sudden modifi- 
cations which are observed to take place in the form 
of the so-called metabolic Infusoria are in this way 
explained by an analogous phenomenon, so much the 
more evident as the Infusoria which possess this prop- 
erty, show in the cortical layer of their protoplasm 
(ectosarc) granulous bands which have with more or 
less justice been compared to the muscles of the 
higher animals. The displacements of the body de- 
termined by the pseudopodia, by the vibratile cilia, 
and by the flagellum are much more difficult to inter- 
pret; meanwhile it is probable that the movement 
proceeds from the contractions of the protoplasm 
which are produced either in the ectosarc or in the 
motor organ itself; the latter is automobile, as is seen, 
for example, when a flagellum separated from the rest 
of the body continues to move in the liquid. 

It is well known that any number of discussions 
have been raised as to the manner in which the ped- 
icel on which the Vorticelle are mounted, contracts. 
Still more obscure is the oscillatory movement of the. 
Bacteria. These small beings are very mobile when 


OF MICRO-ORGANISMS. 19 


chey find themselves ina liquid; they frequently ex- 
hibit a movement of oscillation which sometimes car- 
ries them forward, sometimes backwards. An attempt 
has been made to explain these movements by postu- 
lating the presence of organs of locomotion, extremely 
slender filaments planted at one of the extremities of 
the Bacteria like small rods; but the existence of these 
organs has not been absolutely proved. Even more 
obscure is the movement observed in certain Grega- 
rines. It would seem that in the case of these ani- 
mals, which are often of considerable size, one ought 
to be able to understand the principle of their move- 
ments much more easily than in the case of such 
small beings as the Bacteria; but this is not the case. 
The Polycystids have a very peculiar manner of mov- 
ing; the motion is one of perfect translation, uniform 
and rectilinear; the animal seems to slide all of a 
piece over the object-plate; it can go to the right, to 
the left, stay its motion and resume it again; it is free 
in directing its movements. Now, during this move- 
ment nothing can be seen to take place in the body 
from within or without. An analogous phenomenon 
is to be observed in the Diatomes. Some scientists 
have wished to explain the mysterious motion by 
translation executed by the Gregarines, as being due 
- to an imperceptible undulation of the sarcode; but if 
there were any undulations whatever, one ought to ob- 
serve a correlative movement in the granules inside; 
now this is something that is never seen. 

Thus there still exists a great deal of obscurity 
concerning the principles determining motion among 
the Proto-organisms. The theories based upon muscular 
contraction that have been propounded from observ- 
ing higher animals, are by no means sufficient to ex- 


20 EB 9 Mines Ea A Ce KERIO: 


plain the phenomena of motility among certain Pro- 
tozoa and Protophytes. 

Nervous System. WHitherto not the minutest trace 
of a central nervous system has been found in a single 
Proto-organism. The nervous function among these 
inferior beings devolves upon the protoplasm, which 
is irritable, which feels and which moves, and which, 
in certain species, as we shall see later on, is even ca- 
pable of performing certain psychic acts, the com- 
plexity of which seems quite out of proportion to the 
small quantity of ponderable matter which serves as 
a substratum to these phenomena. There is, more- 
over, no occasion to be surprised that an undifferen- 
tiated mass of protoplasm should be able to exercise 
the functions of a veritable nervous system. In fact 
every nervous element is nothing else than the pro- 
duct of protoplasmic differentiation; the protoplasm 
embodies in itself all the functions that, in conse- 
quence of an ulterior division of labor among the 
pluricellular organisms, have been assigned to distinct 
elements. 

It has rightly been held, therefore, that if no nerv- 
ous system, anatomically differentiated, existed in 
proto-organisms, it must be admitted that their pro- 
toplasm contains a diffused nervous system. Among all 
the observations that uphold this idea, we must cite 
one to which M. Gruber, a professor at Freiburg, in 
Breisgau, has recently called attention. This obser- 
vation was made on a large, ciliated Infusory, the 
Stentor, of which mention will be made so often here- 
after that it will be advantageous to give a full de- 
scription of it beforehand. 

The Stentor has an elongated body, broadened in 
front like a funnel, and able to fasten itself by its pos- 


OF MICRO-ORGANISMS. . 21 


terior extremity. The edge of its peristome is covered 
by a belt of vibratile cilia disposed about a spiral 
line. The mouth occupies the most sunken part of 
the peristome. 
The body of the animal is striated with longitudi- 
nal bands; at the plane of the peristome, these bands 
take a different direction: they become transversal and 
spiral. In the interior of the protoplasm can be ob- 
served a contractile vacuole and a nucleus like a string 
of beads, made up of a large number of grains. This 
Infusory, like all the Ciliates, mul- . 
tiples by fission; a contraction is 
seen to take place in the middle of 
the body; the segment below the 
contraction generates a peristome 
similar to that of the upper seg- 
ment; then a second contractile vac- 
uole is formed, and soon the two 
segments represent two complete 
animals which possess all their or- 
gans. Nevertheless, the two Sten- 
tors continue to be united for a cer- 
tain length of time by a bridge of 
matter, located even with the point 
where the contraction took place; 
this bridge of matter gradually 
grows thinner and thinner and be- 
comes as fine as a thread. (See 
fig. 5.) Now, Gruber has observed 
that the two Stentors united by this ’s- 5. Stentor in pro- 
_ bridge of protoplasm exhibit perfect perso tieion: 
harmony in their movements; they always sway in the 
same direction at the same time; and this harmony is 
necessary, because the least contrariety of motion 





22 LHL PS¥YCHLIG LILLE 


would suffice to break the feeble bond that unites 
them. Moreover, their vibratile cilia beat in unison. To 
explain this concordance in the movements of the twa 
animals, Gruber assumes that the entire mass of their 
protoplasm performs the function of a diffused nervous 
system, which has the effect of regulating their move- 
ments and of making them harmonize. 

We might add that the Infusoria possess not only 
a diffused nervous system, but that they must of neces- 
sity possess special nerve centres, endowed with dif- 
ferent functions. 

It will be remembered in fact that, under the influ- 
ence ofcertain poisonous agents, death is not simultane- 
ous throughout all parts of the organism. What 
ceases first are the voluntary movements of the large 
cilia; the movements of the small cilia are able to per- 
sist much longer; and finally, when all the cilia have 
become immobile and rigid, the vesicle has still been 
seen to pulsate for an hour. This gradual death re- 
calls what we remark among the Vertebrates; under 
the influence of poisonous agents, the brain dies first, 
then follows the marrow, and lastly the bulb, which is 
the wl/imum mortens. . 

The Organs of Sense. All the Micro-organisms 
are endowed with sensibility; some, like the Infusoria, 
have exceedingly sensitive powers. But, hitherto, 
organs of sense anatomically differentiated have been 
found in only a very small number of species. Gen- 
erally, the protoplasmic expansions which we have 
above described under the name of pseudopodia are 
regarded as fulfilling the function of rudimentary 
organs of touch which advise the micro-organism of. 
the presence of objects which happen in its path; but 
these pseudopodia, which at the same time serve as 


OF MICRO-ORGANISMS. Za 


motor apparatus, do not exhibit any structure which 
especially fits them for the reception of sensory im- 
pressions. Similarly, Stein considers the vibratile 
cilia as organs of touch. As these are organs which 
have not undergone any differentiation, we shall not 
stop to consider them. The Infusoria belonging to 
the genus Cryptochilum (Maupas) carry at their pos- 
terior extremity a long rigid bristle, which M. Maupas 
regards as an organ of touch, intended to advise the 
animal of the approach of other Infusoria. 

We shall speak more at length of the organ of 
sight; this has been the subject of numerous treatises, 
some of which are quite recent and of the greatest 
interest to general physiology and psychology. Of 
all the organs of sense the eye is the one which is 
first differentiated. It is found in the organisms be- 
longing to the vegetable kingdom as well as in those 
belonging to the animal kingdom. While these small 
beings do not seem to possess any organ especially 
adapted by its structure for the reception of tactile, 
olfactory, or gustatory impressions, a large number 
already exhibit an ocular spot, that is to say a differ- 
entiated organ, for the purpose of sight and for no 
other purpose. 

Let us first turn our attention to the eye of the 
Protozoa. 

It is chiefly in the group of Flagellates, and prin- 
cipally in the species that are colored green by chlo- 
rophyl (for example the Euglenz), that ocular spots 
are found; these spots which are colored a bright red, 
present themselves very clearly to the observation, 
for they are set off by the uncolored plasma of 
the anterior part of the body where they are generally 
located. Oculiform spots are also found in the species 


24 TA EOP SVC. C Sits 


colored by yellow chlorophyl (Uroglena volvox, etc.). 
Generally, there is only one spot, situated at the base 
of the flagellum. This is seen especially in the Euglena 
viridis, a small flagellate infusory, which is very 
abundant in fresh waters, which it often covers with 
a thick green coating. 

In the Synura uvella, a colony-forming flagellate, 
there exist in each individual, in the anterior part of 
the body, numerous spots, varying from two to ten. 

Below we give an illustration representing the 
anterior extremity of the Auglena Ehrenbergii, ac- 
cording to Klebs. A large ocular spot is noticeable, 
in contiguity with the contractile reservoir. Ehren- 
berg, deceived by the appearance of these two or- 
gans, had taken the contractile reservoir for a nerve 
ganglion. 

It is not only in the large 
group of Protozoans that the red 
spots are met with; they are 
found also among the vegetable 
Micro-organisms. A large num- 





ber of green-colored zodéspores 
exhibit at the anterior, and Fig. 6.—Anterior extremity of 


: ; the. Buclenabaroalen reciente 
usually colorless, extremity of Kiebs° sik SK EEE A 


their: bodies, a. smallsréd* point Guaitesotic: ooh leon 
which seems to have exactly the ecole raed 

same structure as the red spot of the Euglene. It was 
on this fact that Stein based his opinion that the 
spot of Euglena is not an eye; to him it seemed im- 
possible to admit that the vegetable Proto-organisms 
could possess a visual organ. This is an excellent 
instance of a préor? reasoning. Later on we shall. 
see that Stein’s view has now been completely 


abandoned; the very opposite view is taken, for the 


OF MICRO-ORGANISMS. 25 


eye of the Protista is considered as being destined to 
perform chiefly a vegetable function. 

Klebs was able to study the structure of the ocular 
spots, by employing a very ingenious artifice. When 
the Euglene are treated with a solution of sea salt, in 
the proportion of one part to one hundred, an enor- 
mous dilatation of the contractile vesicle, which forms 
a hollow in the protoplasm of the animal, is induced; 
now, as the red spot is, so to speak, glued to the vesi- 
cle, it undergoes the same dilatation as the latter does, 
thus greatly facilitating observation. By this treat- 
ment it has been observed that the spot is a small dis- 
coid or triangular mass, of jagged and irregular out- 
line; it is formed of two material parts; for a base it 
has a small mass of reticulated protoplasm, and in the 
meshes of the protoplasm there are small she of an 
oily substance, colored red. 

This red pigment, which has received the name of 
hematochrome, is not without its analogy with the 
green pigment of the chlorophyl, because this latter 
becomes red under certain conditions. For example, 
the chlorophyl pigment which fills the entire body of 
the Hematococcus pluvialis becomes red, when the 
animal enters into astate of rest; the stagnant spores 
of the alge also assume ared tint. So, also, in nu- 
merous plants, the parts of the flower destined to be- 
come red are green as long as they are enclosed in 
the bud. It is thus probable that the red pigment of 
‘the Euglenoids is derived from a green pigment. 

What is the physiological significance of these 
spots? Ehrenberg considered them as eyes; hence 
the name Luglena (word for word, pretty eye), which 
he had given to a species of Flagellates provided with 
ocular spots. This interpretation had been anestioned 


26 LILLE PSVCHIC LITE 


by all the authors of his time, especially py Dujardin. 
At the present day, however, naturalists have come 
back to it, in consequence of observations which have 
been made on other Micro-organisms that possess a 
more perfectly developed eye. | 

M. Pouchet has discovered in the Glenodinium 
polyphemus, which belongs to the group of Peridinia 
(or Dinoflagellates, according to the classification of 
Biitschli), an eye about the function of which there 
can be no mistake. 

This eye occupies a fixed place in the cellule of 
the Peridinium; it has a uniform location and position. 
It consists of two parts, the one a veritable crystalline 
humor, and the other a veritable choroid. The cry- 
stalline is a strongly refracting, hyalin, club-shaped 
body, rounded at its free end, which is always directed 
forwards, while the other end is immersed in the mass 
of pigment which represents the choroid. This latter 
is clearly determined; it forms a sort of hemispherical 
cap, enveloping the posterior extremity of the crys- 
talline. In one of the two forms of Glenodinium pol- 
yphemus, the choroid pigment is red; in the other it 1s 
black. , 

M. Pouchet has been able to establish that in the 
young animals the crystalline is first formed of six to 
eight refracting globes, which are merged into each 
other in order finally to constitute one unified mass. 
Also, the choroid is the result of a combination of the 
pigmentary granules which, at first sparse, group to- 
gether and finally form the hemispheric cap that covers 
the posterior extremity of the crystalline. 

In fact, the visual organ of this Peridinium is com- 
posed of exactly the same parts as the eye of a meta- 
zoon with one exception, the absence of the nerve 


OF MICRO-ORGANISMS. 27 


element. This is not at all differentiated, but remains 
diffused, like the whole nervous system. M. Pouchet 
calls attention to the interest which his observation 
affords trom a taxonomic point of view. The Peri- 
dinia have sometimes been classed among the vege- 
tables; the presence of starch and of cellulose in their 
protoplasm has induced Warming to classify them 
among the Diatomacee and Desmidiacez. It is ad- 
‘mitted to-day that certain Peridinia possess an eye, 
an organ which has hitherto beén considered as the 
exclusive attribute of animals. Nothing more clearly 
emphasizes the altogether artificial character of the 
distinction between animals and vegetables than the 
results of dealing with Micro-organisms. 

Before leaving the Peridinia, we would remark 
that these small beings afford an interesting fact from 
the point of view of the history of the Protozoa; they 
are provided with a long flagellum; they exhibit in ad- 
ditionan equatorial line on which formerly a crown 
of vibratile cilia was thought to be recognizable: this 
supposed co-existence of a flagellum and of cilia had 
determined the naturalists to form a group of Cilio- 
flagellates, serving as a transition between the Fla- 
gellates, properly so-called, and the Ciliates. Since 
then it has been discovered that the Peridinia do not 
possess vibratile cilia; what had given rise to this er- 
ror is the presence of a second flagellum on the level 
of the transverse line which we have just described; 
the movements of this flagellum have the appearance 
of vibratile cilia in motion. 

Some time before the investigations of M. Pouchet, 
M. Kiinstler (of Bordeaux) had discovered, in a Fla- 
gellate of the genus Phacus, a red eye which is also 
formed of two parts; it is composed of a homogenous 


28 THES SY CHI COLLIE 


globule, acting as acrystalline humor, and surrounded 
by a red pigment, acting the part of the choroid. 

Before M. Kiinstler, Claparede and Lachmann, 
in their important work on Infusoria and Rhizopods, 
had described a similar visual organ in the Freza ele- 
gans, a ciliated infusory of the family of Stentorines. 
‘Immediately behind the point of truncation,” say 
they, “there is found a lunate spot of intense black, 
evidently belonging to the category of these phenom- 
ena which M. Ehrenberg, in the Ophryoglene, for ex- 
ample, calls an eye or an ocular spot. The significance 
of this spot has never been known. It was often very 
much denser than that of the Ophryoglene, and some- 
times there was discovered behind it a very trans- 
parent corpuscle, which involuntarily gave rise in the 
mind to the idea of acrystalline humor. We cannot, 
however, add much of importance to this idea, since 
the functions of a refracting apparatus must neces- 
sarily remain problematic, as long as we do not dis- 
cover behind it a nervous apparatus fitted to perceive 
the impressions received.” 

This last conclusion seems to us excessively cau- ’ 
tious. The co-existence of a pigment and ofa crys- 
talline humor amply suffices to characterize a visual 
organ. As to the nerve apparatus susceptible of per- 
ceiving impressions, it is replaced by the protoplasm, 
which, as is well known, is sensitive to light. 

Even before that, in 1856, Lieberkiihn had discov- 
ered in a ciliated infusory, the Panophrys flavicans, 
an ocular spot, composed of a convex crystalline 
humor, having the form of a watch-crystal enveloped 
by pigment and placed on the convex side of the oral 
fosse. In another species, the Ophryoglena atra, he 
found black pigment, but no crystallme humor. 


OF MICRO-ORGANISMS. 29 


It is impossible to believe that these organs are 
not eyes, for they have the same structure as the eyes 
of comparatively higher classes of animals, such as 
certain worms, turbellaria, rotifers, lower-class crusta- 
ceans, etc; all these organs are similarly formed of a 
small crystalline globule enclosed in a small mass of 
pigmentary matter. The identity of structure natur- 
ally leads to the assumption of the identity of 
functions. 

The eye of the Euglena is the simplest of all; it 
is even reduced to the maximum point of simplicity, 
as itis composed of a spot of pigment. What induces 
us to believe that this spot is a visual organ, is the 
presence of this pigment. In fact this pigment is 
found in the most elementary visual organs. Asecond 
argument might be advanced; the red pigment of the 
Euglena exhibits the same re-actions as the coloring 
matter that fills the rods of the retina in the Verte- 
brates. From among these re-actiorfs common to 
both, we cite the decoloration under the influence of 
light (Capranica). 

Whatever the case may be, one thing is certain, 
namely that the Euglena is very sensitive to the 
light. When they are kept in a vessel, they are in- 
variably seen to cover the side exposed to the light. 
M. Engelmann has observed that light acts very 
strongly upon this small animal; it does not act 
directly on the spot of pigment, nor, as was formerly 
thought, on the flagellum, but on the protoplasm which 
is located in front of the spot. The special micro- 
spectral object-glass that M. Engelmann constructed, 
enables us to see that the Euglene always congregate 
in the band F to G of the spectrum. 

So far as the vegetable Micro-organisms are con- 


30 THE PSY CHLCRl Lite. 


cerned, we have already mentioned that a large num- 
ber of the algz zodspores exhibit, in the anterior part 
of their body, ocular spots of a beautiful ruby color: 
these are organs that probably have the same struc- 
ture as the red spots of the Euglene. Moreover, it 
is probable that certain Microphytes possess more 
complex visual organs, composed of red pigment and 
of a crystalline humor. M. Balbiani has recently 
testified to this fact in the case of the Pandorina mo- 
rum, a spherical colony of green micro-organisms; in 
each colony there exists a certain number of individ- 
uals which possess a red spot, the shape of which is 
perfectly circular; if this spot be examined under a 
glass of very high magnifying power, one can readily 
see that it is formed of a small spherical globule, cov- 
ered, on a portion of its surface, by acap of red 
matter. This observation is all the more interesting 
because it is made on a being, the vegetable nature of 
which is to-day no longer doubted; the Pandorina are 
Volvocinz which modern botanists place.among the 
alge. (Weare glad to give our readers the earliest 
communication concerning this fact.) 

In describing the eye of the Protista, we said that 
the eye is the only organ of sense which is distinctly 
differentiated in these lower beings. But, perhaps, 
this assertion is too sweeping. Some species appear 
armed with small organs which could easily be in- 
vested with a sensory function. In this respect, we 
may cite the Loxodes rostrum, a beautiful ciliated in- 
fusory, remarkable for its proboscis and for the mus- 
cular sheath which closes its mouth. This animal 
exhibits along the dorsal surface a row of small organs 
which, by their structure, seem destined to act a part 
in performing the function of hearing. They are 


OF MICRO-ORGANISMS. seh 


formed of a vesicle, the centre of which is occupied by 
a refracting globule; they are called the vesicles of 
Miiller, after Johannes Miiller, who discovered them. 
The auditory organs which have been observed in 
Worms and the Coelenterata are apparently composed 
of a vesiculiform capsule enclosing a solid concretion, 
called otolith. Thus it is possible that the vesicles of 
Miller may be auditory vesicles. Up to the present 
time this organ has not been met with in any other 
species of Protozoa. 


ahs 


NUTRITION. 


After studying the organs, let us pass to a study 
of their functions. 

It is not our intention to devote special chapters to 
irritability, instinct, memory, reasoning, and the powers 
of volition in Micro-organisms. This would lead to 
diffuseness of treatment. Our method will be quite 
different. We shall describe as a whole all the dif- 
ferent manifestations of psychical activity attendant 
upon the actions of Micro-organisms in the exercise 
of the important functions of their existence. The 
present chapter will be devoted to psychical phe- 
nomena connected with the act of nutrition. 

All living matter possesses the power of continu- 
ally increasing its mass by the inward reception of 
materials, and of simultaneously decreasing the same 
through the combustion of its substance with the 
oxygen of the atmosphere. The first of these pro- 
cesses is called nutrition, and the second, respiration. 

We shall first examine the psychical phenomena 
which precede and determine the act of respiration. 
These phenomena are often very simple and of little 


32 LULL IES Y GAL C eens 


significance. If the Micro-organism lives in the 
water, which is most frequently the case, the oxygen 
contained in solution therein passes directly through 
the cellular cuticle by dialysis and comes in contact 
with the body of the protoplasm; in which case the 
process of respiration is solely a chemical phenome- 
non. But it may happen that a minute organism 
chances into a medium containing little or no oxygen- 
gas; amid these new conditions where it becomes nec- 
essary to move towards sources emitting oxygen by 
voluntary effort and directed motion, it has been dis- 
covered that a great number of Micro-organisms, and 
particularly Bacteria, are capable of detecting the ex- 
pansive power exerted by oxygen in the liquids in 
which they are found. When bacteria of putrefied 
matter are put in a drop of water containing no oxy- 
gen but in which have been placed chlorophyll alge, 
or green Euglenz, or grains of chlorophyl obtained by 
crushing green cellules, nothing happens in the first 
instant; but if the preparation.-be illuminated so as to 
allow the chlorophyl to act, the bacteria are seen to 
exhibit very rapid movements and to proceed, al- 
together, towards the points of the preparation where 
the generation of oxygen is taking place, that is to 
say, about the grains of chlorophyl. Under these con- 
ditions a chemical exchange is instituted between the 
chlorophyl and the aérobious Bacteria: the Bacteria 
disengage carbonic acid gas and absorb oxygen; the 
chlorophyl fastens upon the carbon of the acid and 
sets the oxygen at liberty. If the preparation be 
darkened the Bacteria cease assembling about the 
chlorophy! grains, which, hid from the light, cease to 
disengage oxygen. The clustering begins anew, ifa 
ray of sunlight is again let touch the chlorophyl. 


OF MICRO-ORGANISMS. 33 


Analogous facts have been observed under circum- 
stances somewhat different. In a preparation from 
the intestines of a silk-worm, M. Balbiani has seen 
Bacteria which were uniformly distributed throughout 
all points of the preparation, gather about the green 
and undigested cellules of the leaves contained in the 
intestines, and bury themselves in them as if to par- 
take of them. In other instances, the same naturalist 
has observed that Bacteria developed in a drop of 
silk-worm’s blood, would gather, after a while, about 
the globules of the blood; undoubtedly for the purpose 
of seizing the oxygen being absorbed by them. 

Upon the basis of these facts M. Engelmann has 
established the method called the Bacteria method. 
He regards bacteria as a living reagent which enable 
us to reveal the trillionth part of a milligram of oxy- 
gen, that is to say, a quantity scarcely greater, accor- 
ding to the calculations of physicists, than a molecule. 
This curious method enables us to explain biological 
problems which had hitherto remained unsolved. 
Before this, it was not known whether the colorless 
protoplasm of green plants could or could not disen- 
gage oxygen. It is now known, thanks to the bacte- 
ria, that grains of chlorophyl are the only points about 
which the liberation of oxygen takes place. The same 
method has enabled us to prove, in the variegated 
plants, that the maximum liberation of oxygen coin- 
cides with the maximum absorption of light. Thus, 
in the case of green alge, the red and the violet colors 
of the spectrum are the spots where the bacteria ac- 
cumulate the thickest; consequently here is where the 
liberation of oxygen is greatest. Now, these colors 
correspond to the lines of greatest absorption in the 
spectrum of chlorophyl. In the case of brownish vel- 


34 THE PSYCHIC LIFE 


low cellules, the maximum ‘action is in the green; in 
the case of bluish green cellules, in the yellow; in the 
case of red cellules, in the green. The author has 
concluded from this that there exists a series of col- 
oring substances which, like chlorophyl, have the 
power of resolving carbonic acid gas; he calls them 
chromophyls. In the same way, moreover, this method 
enables us to solve the question of the distribution of 
energy in the solar spectrum. As M. Engelmann has 
remarked, it is interesting to see the Bacteria come to 
confirm our theories as to the composition of solar 
hight. 

Bacteria are not the only organisms that eagerly 
make towards points where oxygen is to be found. 
A large number of other Micro-organisms act in the 
same way when they happen into a medium lacking 
oxygen. M. Ranvier has noticed that if a preparation 
containing leucocytes, screened from air, be examined 
for a certain length of time the cellules will be*seen to 
throw out long filaments towards the part that faces 
the air-side of the preparation. It appears, then, that 
a rudimentary oxygen- sense exists in the protoplasm 
of Proto-organisms. 

This sense does not merely apprise the organism 
of the presence of oxygen; it enables it, further, to 
gauge the tension (expansive power) of the gas. So 
that, when the tension becomes too powerful, the or- 
ganisms are seen to flee before it. 


1B Bie 


The mode of nutrition among Micro-organisms is 
not uniform—a fact which ought not to appear remark- 
able when we bear in mind that this immense group is 
made up of all manner of heterogeneous beings that 


OF MICRO-ORGANISMS. 35 


have nothing in common save the microscopic little- 
ness of their bodies and. the simplicity of their 
structure. Three main types of nutrition may be 
briefly distinguished. 

1. Vegetable nutrition, or according to Biitschlh’s 
expression, holophytic. This is the method of nutri- 
tion among animal or vegetable cellules that contairm 
chlorophyl and that nourish themselves by forming 
organic nutriment from ingredients taken from the 
surrounding medium. It is hardly necessary to call 
to mind that the function of chlorophyl is that_of nu- 
trition and not of respiration. This phenomenon was 
formerly termed the diurnal respiration of plants. The 
expression involves several mistakes. Enough to say 
that vegetables respire as animals do, by uniting with 
oxygen, and that that respiration continues the same 
both day and night. The function of chlorophyl is by 
no means respiration; its office is to decompose the 
carbonic acid gas of the air and to seize the carbon, 
which serves the plant in forming ternary or qua- 
ternary substances. This chemical work is performed 
by all chlorophyl organisms when influenced by the 
radiation of light. , 

Chlorophyl does not belong exciusively to the veg- 
etable kingdom. A large number of animal Micro- 
organisms are colored green by this pigment; they are 
met with principally in the important group of Fla- 
gellates. Their assimilative organs, which are like- 
wise found in all green plants, bear the name of chro- 
“matophores; they have lately formed the subject of 
interesting investigations. 

The chromatophores are small bodies of protoplasm 
which are distinguished from protoplasm in general 
by their having assumed an individual structure. 


36 THE PSVCHIC LIFE 


These little bodies, which in the vegetables are called 
Jeucites, have a granular and reticulate structure; they 
are impregnated with a coloring substance, at times 
green, at times yellow, and at times brown, as the case 
may be; in fact, several coloring substances are 
present, which, by intermixture in different propor- 

«tions, form colors of many varieties. The best known, 
after green chlorophyl, is yellow chlorophyl or dato- 
min. The latter coloring substance can be absorbed 
by alcohol. 

The Euglenoidide, the Chlamydomonadide, and 
the Volvocine exhibit enormous chromatophores. In 
the case of the Euglene, the chromatophores are 
formed of small discoid plates; they are situated di- 
rectly under the cuticle, so that the light can act 
upon them (see fig. 4). In certain-species of Flagel- 
lata, they are exhibited under the cuticle in the form 
of two large plates which envelop the protoplasm 
like a cuirass formed of two pieces. The Chlamydo- 
monadidze and the Volvocine have green chromato- 
phores, disc-shaped, and very small. 

In the centre of the chromatophore a small bright 
space is observed which was formerly thought to 
be filled with chlorophyl; in reality, itis a minute solid 
globule which shows an extremely close analogy with 
the substance composing nuclei, or nuclein. It ex- 
hibits the same chemical reactions; it actively absorbs 
coloring matter and grows extremely brilliant when 
treated with acids. Schmitz gives this little body the 
name of pyrenoid (from pj, nucleus). It is around 
the pyrenoid, and probably through its action, that 
starch forms; it is deposited in grains or re-unites in a 
ring about the pyrenoid, a fact easily ascertained by 
coloring them with iodine. 





OF MICRO-ORGANISMS. 37 


Production of starch has also been observed in the 
colorless Flagellates, as for instance in the Polytoma 
uvella. ‘These latter do not have chromatophores, but 
Kinstler, and after him Fisch, has noticed that every 
grain of starch is attached to a small mass of colorless 
protoplasm which is the focus of formation for the 
grains. This is precisely what happens in vegetable 
organisms where colorless starch-leucites are found: 
This little mass of protoplasm always faces the hilum 
of the starch-grain. 

As the function of the chromatophores is exercised 
only when subjected to the influence of light, it fol- 
lows that green Micro-organisms must have light in 
crder to nourish themselves. 

A quite remarkable fact may be adduced in this 
connection. On examining the kingdom of Protozoans 
as a whole, it will be seen that a striking coincidence 
exists between the presence of the eye and the 
presence of the chlorophyl pigment. Organisms hav- 
ing an ocular spot are in most cases provided with 
the chlorophyl pigment, or, in other words, nourish 
themselves as plants do, by generating starch through 
the action of light. This fact proves that sensibility 
to light is in some manner dependent upon the 
chlorophyl function. If Flagellates possessing chro- 
matophores, that is organs generating starch, have 
ocular spots at the same time, it is because these ru- 
dimentary eyes-enable them to find their way 
towards the light, which is the necessary agent of 
chlorophyl action. Accordingly, all Micro-organisms 
having eyes nourish themselves as plants do. In their 
case, the object of the eye is to direct the performance 
of a vegetable function. 

It is interesting to note in this connection that the 


38 LAT EX PSV CHL CRLTAL! 


Euglene might nourish themselves as animals do, 
for they have a mouth and a digestive apparatus. 
The buccal, or oral, aperture opens in the anterior end 
at the base of the flagellum, and is connected with a 
short gullet or esophagus (see fig. 6, the mouth and 
gullet of an Euglena). Nevertheless, the Euglena is 
never seen using its mouth for swallowing alimentary 
particles. A quite curious problem is involved here. 
If it is true, as has been claimed, that it is the function 
that makes the organ, how do we explain the existence 
and especially the genesis of this digestive apparatus 
which performs zo function? 


It.is the presence of chromatophores that prevents 
certain Flagellates from feeding hke animals; somuch _ 
so in fact, that the digestive apparatus performs its 
functions in Flagellates which have no chromato- 
phores and are not provided with chlorophy! pigment, 
an instance of which is seen in the Peranema. ‘The 
Peranema is, further, an exceedingly voracious animal. 
We must note also that the Peranema does not exhibit 
ocular spots like the green Euglena; and moreover, it 
has no need of such, since it does not have to seek the 
light to generate starch. All these phenomena are 
interdependent. 


The influence exerted by light upon the green 
organisms of both kingdoms has been ascertained 
by different scientists. Light at a certain degree 
of intensity attracts them, and at a greater de- 
gree, repels them. Some years ago M. Strassburger 
conducted a series of connected experiments upon the 
movements of green spores towards light. It was ob- 
served, here, that the grains of pigment in the in- 
terior of the cellules, when under the influence of 


OF MICRO-ORGANISMS. 39 


solar radiations, executed movements and set out- 
wards in all directions. 

2. Nutrition by endosmosis, or saprophytic. The or- 
ganism nourishes itself by absorbing through the 
whole surface of its body liquids containing the pro- 
ducts of vegetable or animal decomposition. Sapro- 
phytic beings are found in putrid waters or in infu- 
sions. This manner of nutrition may be considered, 
from the point of view which now engages us, as the 
most simple of all; it probably allows of a search for 
food, but it is certain that no movements are involved 
which are designed to draw the food into any possible 
digestive apparatus. 

3. There is now a.last mode of nutrition, of which 
we shall treat in minute detail; namely, animal nu- 
trition, where the Micro-organism seizes solid alimen- 
tary particles and nourishes itself after the fashion of 
an animal, whether it be by means of a permanent 
mouth or by means of an adventitious one, improvised 
at the moment of need. This manner of nutrition is 
the process employed by higher animals. Among the 
lower organisms, it is met with in most of the In- 
fusoria, in the Sarcodines, in many of the Mastig- 
ophores, and in others. Respecting the Micro-organ- 
isms. belonging to the vegetable kingdom, we find 
nutrition by endosmosis and chlorophyl nutrition; 
the Protophytes never possess a mouth and never 
absorb solid foods. 

Animal nutrition requires very remarkable psy- 
chological faculties in the organism practicing it. 
These manifestations of psychic life, the progressive 
complexity of which we intend to trace in starting 
from the simplest protozoic forms and arriving at the 
higher—prove that these animalcula are endowed with 


40 THE RSV CHL LT Las 


memory and volition. We shall group our remarks 
under the two following heads: 

a. The choice of food; and 

2. The movements necessary for the prehension of 
food. | 

The Micro-organisms do not nourish themselves 
indiscriminately, nor do they feed blindly upon every 
substance that chances in their way. Also, when they 
ingest food through some point or other of their bodies, 
they understand perfectly how to make a choice of the 
particles they wish to absorb. This choice is some- 
times quite well defined, for there are species which 
feed exclusively upon particular foods. Thus, there 
are herbivorous Infusoria and carnivorous Infusoria. 
Among the herbivorous ones may be classed the chilo- 
dons which feed upon small Algze, Diatomacez, and 
Oscillaria. The parmecia live principally upon Bac- 
teria. The Leucophrys is a specimen of the carnivo- 
rous class; it devours even the smaller animals of its 
own kind. The Cyrtostomum leucas eats everything, 
as do the Rotifers. , 

Though the fact of an exercise of choice in taking 
food is settled beyond question, yet the interpreta- 
tion of this phenomenon is a matter of much uncer- 
tainty.’ Some writers, as Charlton Bastian for in- 
stance, explain this choice of food as an affinity of 
chemical composition existing between the organism 
and the nutriment. This idea does not lead to any- 
thing. Others compare the discrimination made by 
the Proto-organism between objects presented to it, 
to the action of a magnet which in some way selects 
particles of iron that have been mixed with particles 
of other substances. The latter interpretation is an 
evidence of the tendency evinced by some naturalists, 


OF MICRO-ORGANISMS. 41 


of endeavoring to identify the attributes of living or- 
ganic matter with the physico-chemical properties of 
the mineral kingdom. 

In our opinion, the only question demanding con- 
sideration is whether the choice of food, in the case 
of Proto-organisms, does or does not result from a 
psychical operation, similar, forexample, to that which 
takes place in higher organisms. We have received 
a noteworthy communication from M. E. Maupas, 
upon this subject, which tends to establish that the 
choice of food is not the result of individual taste in 
the Micro-organisms, but is determined by the or- 
ganic structure of their buccal apparatus which does 
not allow them to receive other forms of nutriment. 

We must closely examine, therefore, the mechan- 
ism for prehension of food. . 

The following is what occurs when the Amceba, in 
its rampant course, happens to meet a foreign body. 
In the first place, if the foreign particle is not a nutri- 
tive substance, if it be gravel for instance, the amceba 
does not ingest it; it thrusts it back with its pseudo- 
podia. This little performance is very significant; for 
it proves, as we have already said, that this micro- 
scopic cellule in some manner or other knows how to 
choose and distinguish alimentary substances from 
inert particles of sand. If the foreign substance can 
serve as nutriment, the Amceba engulfs it by a very 
simple process. Under the influence of the irritation 
caused by the foreign particle, the soft and viscous 
protoplasm of the Amceba projects itself forwards and 
spreads about the alimentary particle somewhat as an 
ocean-wave curves and breaks upon the beach; to 
carry out the simile that so well represents the process, 
this wave of protoplasm retreats, carrying with it the 


42 FHI PSY CHT G LLL, 


foreign body which it has encompassed. It is in this 
manner that the food is enveloped and introduced into 
the protoplasm; there it is digested and assimilated, 
disappearing slowly. 

There are cellules found in the inner intestinal 
walls of lower animals which effect the prehension of 
solid foods in the same manner as the Amceba cellule: 
they are called phagocytes. 

This mode of prehension is beyond contradiction 
the most simple imaginable; for the prehensile organ 
is not as yet differentiated. Every part of the proto- 
plasm may be made to serve as a digestive cavity in 
enveloping the foreign substance. 

From the special standpoint of prehension of food, 
we may place the Actinophrys sol above the Amceba. 
This animalcule is a small microscopic Ileliozolarian 
abounding in fresh-water ooze. It casts out long, 
slender, filamentous pseudopodia from every part of 
its body. When its prey or any alimentary substance 
gets into the midst of this mass of filaments, the fila- 
ment affected quickly draws back, carrying the nutri- 
tive matter with it towards the body proper of the 
Actinophrys. In other instances, the filaments, anas- : 
tomosing themselves, form a sort of envelope about the 
prey. At the instant the substance comes within a 
short distance of the cellule, a part of the protoplasm 
composing the mass projects itself forwards, and en- 
compasses the food, which is carried back and envel- 
oped in the midst of the protoplasm by a process anal- 
ogous to that seen in Amceba. 

In the case of the Actinophrys any part of the body 
could serve as a way of entry for food, that is to say, 
could act the part of a mouth. To use the expression 
of W. Saville Kent, it is a pantostomate being. In 


OF MICRO-ORGANISMS. 43 


other species of higher organization, this mode of ali- 
mentation is rendered impossible by the cutitcle which 
encompasses the body; tne formation of a cuticle im- 
pervious to solid foods creates the necessity of a buccal 
orifice through which food may enter into the interior 
of the protoplasm. 

A curious graduation in these phenomena is noticed 
here. Thus there are organisms destitute of a per- 
manent and pre-existing mouth; their mouth is 1m- 
provised as the occasion demands, is adventitions, so 
to say, and the reason that these organisms are 
ranked higher than the preceding ones, is that the 
mouth is invariably formed in the same place. 

In this connection we may examine a small flagel- 
late Infusory which abounds in impure waters, the 
Monas vulgaris. It carries a long flagellum attached 
to its anterior extremity, which when not in motion, is 
coiled up against the body. At the base of the flagel- 
lum the protoplasm projects a pellucid substance in 
the shape of a lp. This protuberance is hollow, 
containing a vacuole filled with liquid. Cienkotvski 
has described how these different organs act. The 
Bacteria and Micrococcus, which constitute: the food 
of the AZonas, are pulled into the latter’s neighborhood 
by strokes of the flagellum; at that instant, the animal 
becomes conscious of the proximity of these other 
bodies, forthe protuberance which hes at the base of the 
flagellum extends towards the corpuscule, envelops it 
in its own substance, and pulls it back into the interior 
of the Monad’s body. Bititschli has made an analo- 
gous observation with the Ozkomonas termo. 

The prehension of food comprehends, here, three 
phases, in two of which the organism manifests 
psychical activity: firs/, attraction of food by means 


44 PHE PSY CHLG AAP 


of the flagellum ; second, formation of the vesicle 
which extends towards and envelops the food, when 
the latter has come near; ¢Azrd, absorption of the food. 

The Acinetez are organisms that move about very 
little ; they frequently remain fixed to a pedicle their 
whole life long. They have no cilia, but exhibit ra- 
diating prolongations, more or less numerous, and 
sparse or grouped in tufts, as the case may be. These 
filaments are suckers, provided at the end with a small 
air-hole. When a thoughtless Infusory swims into 
the territory of an Acineta, the latter arrests it by means 
of its stout filaments and fastens upon the former’s body 
the cup-shaped extremities of its suckers, which make 
avacuum. The protoplasm of the Ciliate thus cap- 
tured, slips slowly through the suckers as through 
tubes, and is gathered together in the interior of the 
Acineta in the form of small drops. In the Acinete, 
accordingly, particular organs are adapted to the pre- 
hension and absorption of food. Corresponding to 
the greater complexity of physical action, the psy- 
chical process necessary for the act of prehension has 
likewise become more complicated than is the case 
with the Amceba. The Acineta is obliged to direct 
its sucker towards the Infusory which is within its 
.reach, and consequently the animal is obliged to de- 
termine the position of its prey. 

There are Acinetide that exhibit prehensile or- 
gans more perfect than those just noticed. Such are 
the Hemiophrys. They have both sucker tentacles and 
prehensile tentacles. The latter are filaments which 
the animal throws about its victim like a lasso, thus 
enveloping and rendering it motionless, while it pro- 
ceeds to feed upon it by means of its suctorial ap- 
paratus. 


OF MICRO-ORGANISMS. 45 


Now, do these Acinetide show any preference of 
choice among the Infusoria that chance to fall 
within reach of their tentacles? M. Maupas, who has 
made an especial study of these organisms had at first 
admitted this preference in choice. But he afterwards 
rejected the notion. In 1885, he writes us: “I find 
quite another explanation of the impunity with which 
the Coleps hirtus can throw itself upon the terrible 
suckers of the Podophrys fixa. The stout shell with 
which this little Infusory is enveloped, serves it asa 
shield and guards it from the deadly grasp of the Acine- 
tide. The Acinetide do not seize the Coleps because 
of any dislike of the latter, but because they are un- 
able to seize them, and their inability results from the 
peculiar structure of the Coleps’ tegumentary en-- 
velope. The Paramecia which also escape unscathed, 
are similarly provided with a tegument of high resist- 
ing power, which serves them as a protection in this 
contingency. The Stylonichia histrio, like all other 
Stylonichiz, has a very soft tegumentary envelope. 
They are accordingly seized and devoured by the 
Acinetide without difficulty. The detailed knowledge 
of the differences of structure in the tegumentary en- 
-velopes has caused me to abandon the idea of a pre- 
ference or dislike in the choice of those victims which 
serve as food for the Acinetide. Of the prey that 
passes by, they catch what they can and not what they 
want to.” 

In a large number of species the prehension of food 
is preceeded by another stage, the search for food, 
and in the case of living prey, by its capture. We 
shall not investigate these phenomena among all the 
Protozoa, but shall direct our attention especially to 
the ciliated Infusoria. Their habits are a remarkable 


46 THE PSYCHIC LIFE 


study. If a drop of water containing Infusoria be 
placed under the microscope, organisms are seen 
swimming rapidly about and traversing the liquid 
medium in which they are in every direction. Their 
movements are not simple; the Infusory guides itself 
while swimming about; it avoids obstacles; often it 
undertakes to force them aside; its movements seem 
to be designed to effect an end, which in most instances 
is the search for food; it approaches certain particles 
suspended in the liquid, it feels them with its cilia, it 
goes away and returns, all the while describing a zrg- 
zag course similar to the paths of captive fish in 
aquariums; this latter comparison naturally occurs to 
to the mind. In short, the act of locomotion as seen 
in detached Infusoria, exhibits all the marks of volun- 
tary movement. | 

It might also be mentioned that every species 
manifests its personality in its mode of locomotion. 
Thus, as a rule, the Actinotricha saltans when placed 
in a preparation where it finds itself at ease, remains 
for a few moments perfectly immovable. Then, of a 
sudden, it dashes forward with the rapidity of lght- 
ning and disappears from the field of vision. Fora 
time it darts about to the right and to the left, and © 
then once more assumes its state of immobility. It 
can move with the greatest agility through masses of 
débris, in the midst of which, bending and twisting, it 
slips about with wonderful nimbleness. The Zagynus 
crassicolis, on the other hand, moves along at a pace 
quite constant and uniform, neither slow nor rapid. 
It searches about among alge and fragmentary parti- 
cles. The Perttromus Emme moves slowly. It runs 
lazily over the Alga, where it seeks its nutriment, and 
does not stray from them to venture into the open water. 


OF MICRO-ORGANISMS. 47 


Concerning the prehension of foods and the search 
for nutriment on the part of Ciliates, we can do no better 
than to quote entire a note which M. E. Maupas has 
been pleased to send us upon the subject. We had 
put to him two questions: /7zrs?¢, do the Ciliates hunt 
their food? Second, while in quest of live prey, do the 
Ciliates called hunters make an actual hunt, involving 
the espial of prey from a distance and the voluntary 
pursuit of the same in the circuitous paths they fol- 
low? M. E. Maupas after having once more had re- 
course to observation, briefly recapitulates his opinion 
in the following lines: 

“From the standpoint of prehension of food, the 
Ciliates may be divided into two great groups: 

1. Ciliates with alimentary vortices; 

2. Hunter Ciliates. 

“Tn the first group the mouth is always held wide 
open, and along with the nutritive particles which the 
current of thevortex keeps constantly sucking in, we 
may at will cause other, absolutely inert and indigesti- 
ble, particles to take the same course; for instance, 
such substances as granules of carmine, indigo, and 
rice-starch. These granules, totally unfit for nutritive 
purposes, pass through the body of the Ciliates along 
with the genuine nutriment and are finally cast out 
intact with the excrement. I think, therefore, we 
may affirm that the species having alimentary vortices 
exercise no real choice in selecting their foods, and 
that they absorb indiscriminately all corpuscules which 
by reason of their form and density admit of being 
seized and drawn into the alimentary whirlpool. 

“In the case of the hunter Ciliates proper, the 
mouth is constantly closed. The act of absorbing each 
object captured is accomplished by a process of de- 


48 THLE: PSYCHIC LILI 


glutition comparable in every phase to the like pro- 
cess in higher animals. Furthermore, these species 
feed only upon living prey, which they capture and 
entrammel by means of their trichocysts (wid. Archives 
de Zoologie, Vol. I. 1883, p. 607 and ff.). By this very act 
they exercise a choice in the selection of food. But 
this manifestation of choice is not, in my opinion, the 
result of preference, or of individual taste, but is the 
consequence of the peculiar construction of their buc- 
cal apparatus, which does not enable them to take 
other and different nourishment. 

“These hunter Infusoria are constantly running 
about in quest of prey; but this constant pursuit is 
not directed towards one object any more than an- 
other. .They move rapidly hither and thither, chang- 
ing their direction every moment, with the part of the 
body bearing the battery of trichocysts held in ad- 
vance. When chance has brought them in contact 
with a victim, they let fly their darts and crush it; at 
this point of the action they go through certain manceu- 
vres that are prompted by a guiding will. It very 
seldom happens that the shattered victim remains 
motionless after direct collision with the mouth of its 
assailant. The hunter, accordingly, slowly makes his 
way about the scene of action, turning both right and 
left in search of his lifeless prey. This search lasts a 
minute at the most, after which, if not successful in 
finding his victim, he starts off once more to the chase 
and resumes his irregular and roving course. These 
hunters have, in my opinion, no sensory organ where- 
by they are enabled to determine the presence of prey 
at a distance; it is only by unceasing and untiring 
peregrinations both day and night, that they succeed 
in providing themselves with sustenance. When prey 





OF MICRO-ORGANISMS. 49 


abounds, the collisions are frequent, their quest profit- 
able, and sustenance easy; when scarce, the en- 
counters are correspondingly less frequent, the ani- 
mal fasts and keeps his Lent. The Zagynus crassicolis, 
accordingly, never sees its victim from a distance and 
in no case directs its movements more towards one 
object of prey than towards another. It roams about 
at random, now to the right and now to the left, im- 
pelled merely by its predatory instinct—an instinct 
developed by its peculiar organic construction, which 
dooms it to this incessant vagrancy to satisfy the re- 
quirements of alimentation. 

‘‘The vorticel Infusoria, when in a medium abound- 
ing in food, are almost entirely sedentary in their 
habits, only making slight changes of position. But 
if they are placed in a medium affording but little nu- 
tritive material, they become as migratory as the hunt- 
ers, and are seen to race about in all directions search- 
ing for more abundant nutriment. It is hard to find 
a more perfect illustration of the influence exerted by 
the conditions of a medium upon the habits and 
customs of animals. 

“The Leucophrys patula is a type distinctively car- 
nivorous and possessed of an extremely voracious ap- 
petite, a fact which explains its power of multiplica- 
tion, one of the greatest I have studied. "Withatem- 
perature of 25° in my laboratory I have recently seen ~ 
it separate by fission seven times in twenty-four hours, 
that is to say, a single individual produces from itself 
| just one hundred and twenty eight others in that 
time. In constant pursuit of its prey, it seizes its vic- 
tims by the two stout vibratile lips with which its 
mouth is armed, and swallows them alive and whole. 
The victims may be seen struggling and tossing about 


50 PHEHPSVGHLCCE AI 


for a time in the interior of the Leucophrys’s body 
and afterwards to expire slowly under the action of 
the digestive juices of the vacuole in which they have 
been enclosed. Placed in a medium well-stocked with 
small Ciliates, the Leucophrys have their bodies con- 
stantly crammed with victims swallowed in the man- 
ner above described. Like the other hunter Ciliates 
the Leucophrys does not espy its victims from a dis- | 
tance and does not guide-itself towards them. It 
simply darts about from right to left, every moment 
changing its direction. It thus increases its chances 
of coming in collision ‘with its prey and every time 
that one of its unfortunate victims falls in contact 
with its vibratile lips, it is seized, irresistibly drawn 
towards the mouth and swallowed within less than a 
tenth of a minute.”’ 

Certain hunter Infusoria have methods of pursuit 
and capture which deserve to be examined separately. 
Claparede and Lachman in their excellent work upon 
Infusoria and Rhizopods, have minutely described the 
manner in which a large Infusory, the Amphileptus 
Meleagris, attacks the Hpzstylis plicatilis. The Epis- 
tyfts are colonizing vorticels of which certain individ- 
ual members attain a size of not less than o-21 mm. 
The L£pistylzs form aborescent groups, the ramifica- 
tions of which are quite regularly dichotomous. These 
ramifications all grow at exactly the same rate and the 
individual branches all rise to the same height, rep- 
resenting what is called, in botany, a corymbous in- 
florescence. “We were observing one day,’ says 
Claparéde, ‘‘in the hope of seeing what would come > 
of the manceuvre, an Amphileptus, which was slowly 
creeping upon a colony of Lpistylis. The way-in 
which it approached the Vorticels, feeling them, so to 





; OF MICRO-ORGANISMS. 51 


speak, and partly enclosing them in its pliable body, 
already seemed suspicious. At last, it made a direct 
attack upon one of them by fastening itself upon the 
upper part of its body. It opened its huge mouth, 
which is never to be seen except when the animal is 
eating, and slipped over the /fzszty/7s like the finger | 
of a glove being drawn upon a finger of the hand. 
We saw the sides of the buccal aperture (which are 
capable of being dilated in a truly astonishing man- 
ner) slip slowly over the peristome and upon the body 
of its prey, and then draw together about the point 
where it was made fast to the pedicle. The cilia cov- 
ering the body of the Amphzleptus began to shake with 
that peculiar motion which is always noticed when a 


ciliated Infusory secretes a cyst. At the expiration of 


a moment or so, a fine line was seen to appear around 
the whole body which continued to spread so as 
soon to form the cyst.’”’ (This might be called a cyst 
of digestion.) ‘The phenomenon as a whole is quite 
simple. An Amphileptus approaches an Lfi7stylis 
devours it and encysts itself upon the spot, the 
victim being still attached to its pedicle. It then en- 
deavors to wrench the /fzstylis from its point of at- 
tachment by twisting; it turns on its axis from left to 
right and then from right to left, successively; when 
it has succeeded, it continues its work of digestion, 
and occasionally divides in two within the cyst itself. 
During the last stage of digestion, it rests for a while, 
when it-commences again to turn about in the cyst, 
evidently seeking to disengage itself. At the close of 
a certain number of hours, the cyst breaks. The 
Amphileptus issues forth and starts in quest of another 
victim.’’* 


* Etudes sur les I:ifusotres et les Rhizopodes, Vol. Il. p. 166, 1861. 


ca 


52 THE PSYCHIC LILLE 


The hunter Infusoria are frequently armed with 
trichocysts. Trichocysts are urtical filaments which 
serve the animalcula provided with them to disable or 
wound other micro-organisms. 

A large unmber of Infusoria, the Paramecia, the. 
Ophryoglene, etc., use their trichocysts as organs of 
defense. With other species, of which we shall speak 
more at length, the trichocysts are organs of offense. 
They are located either in the sides of the mouth or 
in parts adjacent thereto; this is the case with the 
Lacrymaria, the Didinium, the Enchelys, the Lagynus, 
the Loxophyllum, and the Amphileptus. 

These latter animalcula attack the live prey that 
constitutes their food, in the following manner. They 
dash upon their victim and bury the trichocysts with 
which they are armed, into its body. The victim is 
immediately brought to a halt, whereupon the hunter 
seizes it and swallows it. So, when the Zagynus Elon- 
gatus intends to seize a victim that has fallen into its 
vortex and has thus been drawn into the neighbor-. 
hood of its mouth, it throws itself swiftly forward. At. 
the moment of contact the hunted Infusory becomes 
suddenly paralyzed and remains perfectly motionless. 
This paralysis is evidently caused by the trichocysts 
which line the esophagus of the Lagynus and with 
which the latter has transpierced its prey at the mo- 
ment it came in contact by its anterior extremity.*” 

In a higher stage of organization, the Microzo6én 
possessing a mouth changes its position in order to 
intercept its prey, and give it chase. 

The Didinium Nasutum (Stein), a carnivorous In- 
fusory and one of the most voracious of our fresh stag- 
nant waters, operates in a more complicated manner: 


* Maupas, op. cit., p. 495. 


OF MICRO-ORGANISMS. 53 


it casts its trichocysts upon its victim from a distance. 
The importance of this instance induces us to stop 
here a moment. 
The Didinium (fig. 7), 
ic, 1, 2S regards the general 
We shape of the body, may 
‘a;" be compared to a dimin- 
utive cask, rounded off at 
one of the ends and term- 
inated at the opposite ex- 
tremity by an almost level 
surface from the midst of 
which rises a conical pro- 
jection quite strongly 
Fig. 7.—Didinium nasutum, enlarged marked. This projection 
two hundred diameters. The figure rep- . Rohe! 
resents a Didinium overpowering a Fa-18 an Organ of deglutition 
ramecium aurelia. The nettle-like fila- : 2 
ments discharged by the Didintum are (swallowing); a longitu- 
seen on all sides ofthe Paramecium; *. te rt : : 
while the latter, already seized by the dinal striation is noticed 
tongue-shaped organ of the Dzdinzumz, is 


being gradually drawn towards the buc- here formed of minute 
cal orifice (after Balbiani). 






solid rods, of extreme ten- 
uity and independent of the sides. These organs 
are the weapons used by the Didznzum in attacking 
the live prey which constitutes its sole nourishment. 
Not only does it attack and devour animalcula 
almost as large as itself, but frequently it even seizes 
individuals of its own kind. In such casesitis always 
| Infusoria, and never the Rotatoria, although the latter 
often abound in waters which the Didinium inhabits. 
It appears, moreover, to have a marked predilection 
for certain species; and so it happens that the huge 








and inoffensive Paramecium aurelia is almost always 
its choice by preference among the animalcula that 
inhabit the same liquid.* 





* The Didinium, Balbiani tells us, never attacks the Parmacium bursaria, 
which is distinguishable from the P. aurelzéa by its green coloration. 


54 THE -PSVCHFCALTLT EEL: 


The prehension of food by the Didinium exhibits 
interesting aspects, which have not as yet been ob- 
served in any other Infusory. M. Balbiani, in his 
first observations, had often been surprised at seeing 
animalcula that the Didinium had passed by without 
touching, suddenly stop as if violently paralyzed; 
whereupon our carnivorous specimen straightway ap- 
proached and seized them with seeming facility. 


More careful examination of the Didinium’s actions ~ 


soon furnished the key to this enigma. If, while 
swiftly turning in the water, the Didinium happens 
into the neighborhood of an animalculum, say a Para- 
mecium, which it is going to capture, it begins by 
casting at it a quantity of bacillary corpuscules which 
constitute its pharyngeal armature. The Parmecium 
immediately stops swimming, and shows no other 


sign of vitality than feebly to beat the water with its 


vibratile cilia; on every side of it the darts lie scat- 
tered that were used to strike it. Its enemy then ap- 
proaches: and quickly thrusts forth from its mouth an 
organ shaped like a tongue, relatively long and re- 
sembling a transparent cylindrical rod; the free, ex- 
tended extremity of this rod it fastens upon some part 
of the Paramecium’s body. The latter is then grad- 
ually brought near by the recession of this tongue- 
shaped organ towards the buccal aperture of the 
Didinium, which opens wide, assuming the shape of 
a vast funnel in which the prey is swallowed up.* 

Up to this point we have paid little attention to 
movements of defence and of flight: Upon this sub- 
ject a few words will suffice. When vorticels are 
alarmed, they are seen to contract forcibly their pedi- 





* Archives de zoologie expérimentale, 1873, Vol. Il, p. 363. Observations sur 
le Diditnium nasutum, by E. G. Balbiani. 


a 


OF MICRO-ORGANISMS. aS 


cle, which in a state of rest stays extended. Infusoria 
placed in a preparation where they are at their ease, 
swim quietly about; if any sharp excitation disturb 
them, they accelerate their pace; those armed with a 
rigid bristle at the posterior extremity, rush precipi- 
tately onward whenever another Infusory chances to 
touch that tactile appendage. The unaggressive Par- 
mecia, when attacked, endeavor to escape, but are 
also able to defend themselves by means of the tricho- 
cysts with which their ectosarc is armed. 


IV. 


Unicellular organisms do not all live in a detached 
state; a large number of species are found grouped 
together in colonies; the initial basis of these agglom- 
erations is always a mother cell, the offspring of which 
instead of dispersing to live at large, remain aggluti- 
nated to-one another. Ehrenberg had believed that 
in certain species (especially in the case of the 4ntho- 
physa vegetans, an aggregation of minute monads 
growing asa sort of bush) the colony was created by 
the union of minute organisms that originally lived at 
large; but observation has shown that his theory was 
incorrect. It may be laid down as a general rule that 
every colony of monocellular animals or vegetables 
spring from the divisions of a single cellule. The 
cellules of one and the same colony, therefore, are 
always sister cellules, and the colony represents a 
family in miniature. 

A leading instance of a colony wholly temporary, 
is found in those organisms the cuticle of which does 
not take part in the phenomena attending the division 
of the protoplasm. In this case, the protoplasm beneath 
the envelope alone divides; the segments resulting 


56 THE PSY CHIL Ce ALS 


therefrom are often numerous, and it is not until the 
plasma has finished dividing that the maternal cuticle 
is destroyed and that the segments separate to live 
abroad in a detached state. Up to that time they re- 
main bound together. 

It is thus seen that the existence of this minute 
colony is a transient phenomenon, which lasts only 
during the time necessary for the division of the ma- 
ternal body. These phenomena have been noticed 
among many of the Flagellates. What appears surpris- 
ing is, that the maternal cellule, although continuing to 
divide beneath the envelope, keeps on moving about 
in the water by means of its own flagellum as if still 
constituting only a single animal. The reason of this 
is that one of the segments into which the plasm is 
divided and which is situated in the anterior part of 
the mother-cellule,.remains connected with the flagel- 
lum and takes charge of its movements. This seg- 
ment (like an individual distinct in itself) alone guides 
the bark that carries its sisters. And so, although 
this diminutive colony is asa rule but short-lived, a 
division of labor has been effected among its mem- 
bers; the anterior segment is alone entrusted with the 
office of locomotion. | 

The colony has a duration less ephemeral in the 
case of the Gontum pectorale, a Volvocine known in 
our fresh waters. It is formed by the aggregation of 
sixteen individuals which remain detached but ad- 
here laterally to one another. The colony is de- 
veloped in one way only: it is in the form of a minute 
rectangular plate of a beautiful green color. In the 
case of the Pandorina, the colony assumes the form of 
a minute sphere; it is composed of sixteen, or as many 
as thirty-two individuals, joined together beneath a 








OF MICRO-ORGANISMS. 57 


stout envelope; each member remains free in action, 
and projects its two flagella through the cuticle. 
With the Ludoryna elegans, the colony is modeled 
upon nearly the same plan excepting that it is com- 
posed of thirty-two individuals and that the latter, 
placed beneath the same cuticle at equal distances 
apart, do not touch one another. 

In the genus Volvox, colonies are found of which 
the structure is very complicated. Such are the great 
green balls formed by the aggregation of diminutive 
organisms, which form the surface of the sphere, and 
-are joined together by their envelopes; they have each 
two flagella, which pass through the enclosing mem- 
brane and swing unimpeded on the outside; the en- 
velopes, each tightly holding the other, form hexag- 
onal figures exactly like the cells of a honeycomb. 
Each Volvox is at liberty within its own envelope; 
but it projects protoplasmic extensions which pass 
through its cuticle and place it in communication 
with its neighbor. It is probable that these proto- 
plasmic filaments act like so many telegraphic threads 
to eStablish a network of communication among all 
the individuals of the same colony; it is necessary, in 
fact, that these diminutive organisms be in communi- 
cation with each other in order that their flagella may 
move in unison and that the entire colony may act as 
a unit and in obedience to a single impulse. The 
number of micro-organisms constituting a Volvox 
colony is quite considerable: as many as 12,000 have 
been counted. 

It was upon analogous phenomena that Gruber 
based the existence of a diffused nervous system in 
the Stentors. The same line of reasoning may be fol- 
lowed in the case of the Volvox. Since unanimity of — 


58 LAE OES VCH GILLES 


movement is demonstrable among twelve thousand 
micro-organisms constituting a colony, it must be in- 
ferred that their movements are regulated by the 
action of a diffused nervous system present in the 
protoplasm. This conclusion is all the more inter- 
esting from the fact that these Volvox are vegetable 
micro-organisms. 
In the dicecian Volvox, the female cellules and the - 
nale cellules are joined together by themselves in sep- 
arate colonies. When the time of fecundation arrives, 
the male cellules or antherozoids scatter and proceed 
to conjugate with the female cellules. The colony 
which bears the female cellules also contains neutral 
cellules which are not designed for fecundation; the 
latter simply perform a locomotive function; equipped 
with one eye and two flagella, they are intended to 
move the great colonial ball: they are the oarsmen of 
the colony. The Volvox, male, female, and neutral, 
all seek the light, whether solar or artificial, and settle 
near the surface of the water. As soon as the female 
colonies have been fecundated, the odspores change 
their color: they turn from green to an orange yellow. 
At this point, the colony is seen to draw away from 
the light and to disappear from the surface of the 
water. This change of position is effected by means 
of the vibratile cilia with which each neutral cell is 
furnished and which project beyond the gelatinous 
sphere; now, as no change of color or form is noticed 
in the neutral cells after fecundation, it may be asked 
from what cause they flee from the light which they 
formerly sought. 
Colonies of Proto-organisms formed by the division 
of a mother cell of which the segments remain united, 
are not entirely without analogy with a pluricellular 


OF MICRO-ORGANISMS. 59 


organism which likewise springs from a single cell 
called the egg, and the resultant divisions of which 
do not separate. : 

The colony constitutes in a way a first step towards 
the physiological constitution of a pluricellular organ- 
ism; it serves to fix a stage of transition in the animal 
kingdom, between Protozoaand Metazoa. A fact which 
strengthens this analogy is, that certain colonies, as the 
Synura uvella and the Uroglena volvox, can divide into 
two other colonies; strangulation acts upon the mass 
just as if upon a pluricellular organism. This curious 
observation was made by Stein and Biitschli. 

Nevertheless, an essential difference still separates 
the Metazoa and the Protozoan colonies, even when 
in these colonies a division of function has been 
established among several individual groups. The 
physiological differentiation brought about in these 
Protozoan colonies is the result of amechanism which 
differs in every respect from that by -which it is 
effected in the case of the Metazoans. In the latter 
instance the differentiation results from the division of 
the embryo into germinative folia each of which is the 
origin of a separate group of organs. At a certain 
stage of development, the superposition of these folia 
- gives rise to the formation of a gastruda; the gastrula 
is formed by two folia joined together, representing a 
pouch open to the outside; it is characteristic of Met- 
azoans, the Protozoan never reaching this stage. Cer- 
tain colonies observed by Heckel, the Wagosphera plan- 
w/a for example, and the volvox, of which we have before 
spoken, appear in the form of a sphere; they suggest 
an anterior stage of development to which the name of 
morula or of blastula has been given; but they do not 
get beyond this stage. 


60 THE PSYCHIC LIFE 


We have now considered assemblages of organ- 
isms which live joined together like the Gonium and 
sometimes united by a material band like the Volvox, | 
“where the individuals are erouped together under 
one and the same cuticle. Voluntary and free combi- 
nations are much more rarely met with; nevertheless © 
cases occur. There exist organisms which lead a life 
of habitual isolation but which understand how to unite © 
for the purpose of attacking prey at the desired © 
time, thus profiting by the superiority which numbers 
give. 

The Bodo caudatus is a voracious Flagellate pos- 
sessed of extraordinary audacity; it combines in troops 
to attack animalcula one hundred times as large as 
itself, as the Colpods for instance, which are veritable 
giants when placed alongside of the Bodo. Likea horse 
attacked by a pack of wolves, the Colpod is soon ren- 
dered powerless; twenty, thirty, forty odos throw 
themselves upon him, eviscerate and devour him com- 
pletely (Stein). 

All these facts are of primary importance and in- 
terest, but it is plain that their interpretation presents 
difficulties. It may be asked whether the Bodos com- 
bine designedly in groups of ten or twenty, understand- 
ing that they are more powerful when united than 
when divided. But it is more probable that voluntary 
combinations for purposes of attack do not take place 
among these organisms; that would be to grant them 
a high mental capacity. We may more readily admit 
that the meeting of a number of Bodos happens by 
chance; when one of them begins an attack upon a 
Colpod, the other animalcula lurking in the vicinity 
dash into tne combat to profit by a favorable opportu- 
nity: 


OF MICRO-ORGANISMS. 61 


v. 

It is difficult in the extreme to mark out the lines 
of a psychology of Proto-organisms from data so in- 
complete as those we have just collected. We shall 
content ourselves with a few brief considerations. 

The apparent result of our investigations up to this 
point is, that the greater number of movements and 
actions observed in Micro-organisms are adrect re- 
sponses to excitations emanating from the medium in 
which they live. Itis the condition of the medium that, 
to all appearance, rigidly determines the character and 
manner of their activity; in a word, they exhibit no 
marks of pre-adaptation. 

But it will not do to let the matter rest with this 
general survey of the subject; we shall have to examine 
more closely each detail of these reflex actions of.adap- 
tation, beginning with the sensory phase and ending 
with the motory phase. Analysis discloses that sev- 
eral determining elements ‘may be distinguished in 
these phenomena; they are: 

1. The perception of the external object; 

2. The choice made between a number of objects; 

3. The perception of their position in space; 

4. Movements calculated, either to approach the 
body and seize it, or to flee from it. 

Weare not ina position to determine whether; these 
various acts are accompanied by consciousness or 
whether they follow as simple physiological processes. 
This question we are obliged, for the present, to forego. 

1. The perception of an external body. Among the 
lowest forms, it appears that perception is always the 
result of a direct irritation produced by contact of the 
external body with the protoplasm of the animalcule. 
This is what takes place, to all appearance, among the 


62 LAE ESVCH iGo Pe 


Amoeba; for these organisms, the condition necessary 
to the perception of a solid particle is contact with it. 
A step forward has been effected in those organisms 
that are able to perceive external objects by contact 
from a distance, as is observed for instance in the 
Actinophrys, which perceives all bodies that chance to 
touch its long filamentous pseudopods; yet, in this in- 
stance, the pseudopod merely acts the part of an ex- 


tended tactile organ. The vibratile cilia, and _ still ' 


more the long lash of the Mastigophores, enable the 
animal to discern the presence of contiguous particles 
at acertain distance from its body, by the pressure 
exerted upon their appendages. It is not known 
whether there are many animalcula that perceive the 
presence of nutriment from a distance and without 
coming in direct contact with it; it appears, however, 
that this is the case with the Didinium which shatters 
its prey from a distance and without touching it. 

2. Choice. We have seen that Micro-organisms do 
not absorb indiscriminately every solid particle they 
meet. They exercise a choice. Among the lower spe- 
cies, the choice is in the lowest degree rudimentary; 
the organism restricts itself to a discrimination of 


mineral particles, sand for example, from organic sub- 


Stances; it rejects the former and absorbs the latter, 
Among the higher animalcula the choice is more in- 
telligent. There are Infusoria that feed only upon 
plants and animals. There are also those which feed 
exclusively upon one species. , 

This exercise of choice is one of the most incom- 
prehensible of phenomena; it is exceedingly difficult 
to explain it without resort to anthropomorphism. If 
we hold to what observation directly teaches us, the 
choice may be said to consist in the following acts: 


OF MICRO-ORGANISMS, — 63 


when aie era eile perceives certain kinds of sub- 
stances and particularly those substances which serve 
it as customary food, it invariably goes through the 
same movement, which consists of an act of prehension; 
when the substance touched, seen, or collided with, 
as the case may be, is of another kind, the Micro-or- 
ganism does not.go through this act. Such is the 
phenomenon; as to the explanation of the same, we 
are unable to give one. 

According to M. E. Maupas, if certain Infusoria 
feed exclusively upon a certain species, it is because 
their buccal apparatus, or organ of prehension, makes 
it impossible for them to feed upon different species 
which possess different tegumentary envelopes. The 
question is to ascertain whether this explanation is 
applicable only in certain cases, as appears very prob- 
able to us, or whether, on the other hand, it is of com- 
plete and universal applicability. We confess that 
the hypothesis of M. Maupas does not explain to us 
why a hunter Infusory that throws trichocysts, like 
the Didinium, attacks the Paramecium aurelia and not 
the Paramecium bursaria. 

It is possible that certain species attract the or- 
ganisms which feed upon them, by means of a phys- 
ical or chemical excitation. 

The researches of Prof. Pfeffer, of the Tubingen 
Botanical Institute, lend a certain confirmation to this 
hypothesis. 3 

3. Calculation of the position occupied by the exter- 
nal body. It isa universal fact that Micro-organisms 
not only perceive external bodies, but that they also 
indicate, by their movements, an exact knowledge of 
the position occupied by these bodies. It might be 
said that they invariably possess a sense of position in 


64 DAL OPS VGHLCCLA EL 


space. The possession of this sense is absolutely in- 
dispensable to them, for it does not suffice them to 
know of the presence of an exterior body in order to 
approach it and seize it; they must furthermore know 
its position, so as to direct their movements accord- 
ingly. 

The simplest form of a sense of localization is met 
with in the Amceba, which, when it closes about a nu- - 
tritive particle, always emits its pseudopods at pre- 
cisely that part of its body where the foreign substance 
caused theirritation. The most complicated instance of 
localization is met within the Didinium, which we have 
so often cited; the Dzdintum knows precisely the po- 
sition of the prey it follows, for it takes aim at the ob- 
ject of its pursuit like a marksman, and transpierces it 
with its nettle-like darts. Between these two species, 
we find all the intermediate instances of a localization 
of perceptions. 

However, doubts exist upon the question as to 
- whether Proto-organisms know the direction and dis- 
tance of external bodies, or whether they only succeed 
in getting at them after a series of tentative move- 
ments. ‘The observations which we have collated do 
not solve the question. 

4. Motory phase.-—We now pass to the motory 
phase. The movements made by Micro-organisms as 
if in response to an excitation, are not in mogt in- 
stances simple reflex motions; they are movements 
adapted to an end. Wecannot repeat it too much: 
these movements are not explained by the simple phe- 
nomenon of cellular irritability. 

In the very first instance, they vary according to 
the excitation; a given excitation produces a corre- 
sponding motory response; a body situated at the right — 


OF MICRO-ORGANISMS. 65 


* 


does not bring about the same movement that a body 
situated at the left does; a particle of the nutritive 
sort does not provoke the same course of action that 
a particle of a different sort does. All this implies 
that associations have been established in the proto- 
plasm between certain excitations. and certain move- 
ments. The explanation of the physical nature of 
these*association appears to us totally impossible. 

The quite ingenious ideas broached by Spencer 
upon the lines of least resistance offered by the com- 
misural fibres cannot be applied here, since everything 
takes place in a single cell. What would be necessary 
to explain is how and in consequence of what mechan- 
ism of structure one form of molecular movement, cor- 
responding to a given excitation, is followed by a cer- 
tain other form of molecular movement correspond- 
ing to an act likewise determined. 


VI. 
FECUNDATION. 


We now enter upon a subject fraught with obscu- 
rity. We shall limit our investigations to ciliated In- 
fusoria, as it is among these species that fecundation 
and the psychical phenomena attendant thereon have 
been best observed. 

Ehrenberg had established by his authority the pre- 
vailing opinion in science that copulation never takes 
place among Infusoria, and that all facts observed by 
early writers as connected therewith are to be re- 
garded as phenomena of longitudinal fissiparity. This 
erroneous idea prevailed unquestioned until 1858, 
when M. Balbiani addressed a communication to the 
Academy of Sciences, wherein he showed that sexual 


66 THE OPS VOHEC LILLE 


reproduction, preceded by copulation, zs found among 
Infusoria. 

Before entering upon a description of the changes 
that take place in the nucleus and nucleole of Infuso- 
ria in coition, we shall briefly sketch the course of 
psychical phenomena through which the ciliated Infu- 
soria pass when making ready for copulation. 

We shall follow in the footsteps of M. Batbiani, 
freely using his descriptions, the exactitude of which 
has since been confirmed by Gruber. 

To appreciate fully the significance of the facts to 
be adduced herewith, we must recall to mind that 
throughout the entire animal kingdom the act of sex- 
ual coition is invariably preceded by an introductory 
manifestation of psychical activity, which may last for 
quite an extended length of time. } 

The female, when pursued by the male, seems to 
be animated by two conflicting desires—that of yield- 
ing to the male and ‘that of repelling his approaches. 
This show of unwillingness, which is but temporary 
and more seeming than real, has the effect of inciting 
the male to attempt an exhibition of powers calculated 
to captivate the female. According to M. Espinas, 
who has thoroughly studied this subject, there are five 
classes of phenomena which assist in preparing the 
way for sexual union: firstly, provocative contact, the 
lowest of all these phenomena—that is, the one which 
‘most approximates to the physiological order; sec- 
ondly, odor; thirdly, color and form; fourthly, noise 
and sound; fifthly, play, or every variety of move- 
ment. It appears to us that almost all manifestations 
of love in human beings themselves could be classi- 
fied into these five categories. 

Among the simplest forms of life we meet with in- 


OF MICRO-ORGANISMS. 67 


cipient traces of such esthetical manifestations point- 
ing towards the preparation of two animals for sexual 
intercourse. 

‘Tt 1s currous,’” remarks M. Balbiani, “to find 
among these organisms which all zodlogists, by reason 
of their diminutive size and extreme simplicity of 
structure, have placed at the remotest limit of the animal 
kingdom, acts that mark the existence of phenomena 
analogous to those by which the sexual instinct is ex- 
hibited in a large number of Metazoans. Upon the 
approach of the period for propagation, the Paramecia 
come in from all points of the fluid and assemble like 
- little whitish clouds in more or less numerous groups 
about the objects that float upon the surface of the 
water, or adhere to the side of the vessel containing 
the tiny artificial sea in which the animalcula are held 
captive. Intense excitement, which the need of food 
does not suffice to explain, prevails in each of these 
groups; a higher instinct appears to dominate all these 
tiny organisms; they seek each other’s company, chase 
each other about, feel here and there with their cilia, 
adhere for a moment or so in an attitude of sexual co- 
ition, and then retire, soon to begin anew. When 
these minute assemblages are dispersed by shaking 
the liquid, they quickly form again at other points..- 
These singular antics wherewith animalcula appear 
to incite each other mutually to copulation often 
continue for several days before the latter act is defin- 
itely effected. 

‘“¢ Other Infusoria, particularly the Spirostomes, seek 
the deep spots of the liquid, or bury themselves in the 
oozy sediment of the bottom, not to come forth again 
until they have separated. The Stentors have differ- 
ent habits. They are affixed by their pedicles to sub- 


68 PALE PSVOH LOLI L SE: 


merged vegetable patches, which they often cover like 
small, closely-mown lawns, of a green, brown, or blue 
color, according to the species; they turn the forward 
part of their bodies, which is elongated in the shape 
of a trumpet, about in all directions, and seek to unite 
with each other by the broadened extremity which 
corresponds to the bell of the trumpet.” 


Among the numerous species forming part of the 
group of Oxytrichine, the act of coition likewise ex- 
hibits certain interesting preliminaries. . The two 
individuals, whose bodies are generally very much 
flattened, and of which the lower sides are provided 
with cilia at times strongly developed, superpose them- 
selves upon each other on the ventral side and mutu- 
ally entangle the cilia which cover that region, while 
with their cornicles, or anterior tentacles, they touch 
repeatedly the different parts of each other’s bodies. 
These introductory moves frequently last for several 
hours before copulation begins. 


As regards the act of copulation itself, it too is of 
exceeding interest to the psychologist, who can ad- 
mire the precision with which the two individuals as- 
sume the attitude necessary for fecundation. 


During conjugation the two ciliated Infusoria are 
‘always joined together at the aperture which forms 
the mouth. It has been thought that this aperture 
must play the part of a sexual orifice through which the 
two animalcula in copulation effected the exchange 
of reproductive matter; it has been suggested, more- 
over, that an especial sexual orifice was present, quite 
close to the mouth; but these questions of structure 
are still doubtful. ; 


The attitude of these organisms during copulation 


OF MICRO-ORGANISMS. 69 


varies according to the position of the mouth which 
in certain groups is lateral and in others terminal. 

The greater number of species have a lateral mouth. 
To this class belong the Paramecia; these Infusoria, 
in which the buccal fosse lies at the bottom of a deep 
excavation made in the ventral face, cover each other 
over the whole extent of this face, exuding a gluti- 
nous substance which causes them to adhere in this 
_ position; the two mouths then lie exactly upon each 
other. Copulation lasts from twenty-four to thirty-six 
hours with the Paramectum aurelia; it lasts several 
days (five or six) with the Paramecium bursaria. 
Among the Oxytrichine, the two animals in conjuga- 
tion blend together at an important part of their per- 
sons in a very intimate fashion. 

We next arrive to the second group of Infusoria, 
which show a terminal mouth; of this type we have 
had a specimen in the Didinium nasutum, the curious 
hunter Infusory; we may further mention the Coleps, 
the Nassula, the Prorodon. The two organisms, in 
this case, do not embrace laterally, they take a posi- 
tion end to end, connected by their anterior extrem1- 
ties, mouth opposite to mouth; then, little by little, 
while still joined at the buccal extremity, they shift 
about until they meet length to length. 

We shall mention particularly, but briefly, the cu- 
rious phenomena that accompany fecundation among 
the Vorticels. Even more than in the instances just cited 
do these phenomena resemble the process of fecun- 
dation in higher animals, for in this instance fecunda- 
tion is effected between two differentiated individuals, 
one of which acts as a male element and the other as 
a female element. The Vorticels are colonies of In- 
fusoria in which are found sedentary individuals, 


70 THE PSYCHIC LALL 


having the shape of minute jugs, and also detached 
individuals called Microgonidia, which are formed by 
repeated divisions upon the colonial tree. 

These Microgonidia have exactly the same mode 
of locomotion as the spermatozoids. Engelmann * has 
followed their movements. He has seen them swim- 
ming about turning upon their axis for five or six 
minutes; then, having come into the vicinity of a Vor- 
ticel, they abruptly change their manner of movement, 
capering about the latter like a butterfly flitting about 
a flower, touching it, retreating, and then approaching 
it again and apparently feeling of it; at last, after 
having visited the others near by, they return to the 
first one and fasten themselves upon its surface. The 
coition is not effected without a certain show of re- 
sistance on the part of the Vorticel. It hastily con- 
tracts the peduncle to which it is attached, at every 
touch of the Microgonidium, while the latter in order 
to prevent itself from being thrown back by these 
rapid shocks and in order to be always close to the 
individual with which it wishes to unite, fastens itself 
by an extremely fine filament to the style of the Vor- 
ticel; thus attached and drawn along with the move- 
ments of the latter, it finally succeeds in effecting a . 
junction with it and in penetrating into its body.+ 

It is now time to describe the material phenomena 
that take place in the interior of the two Infusoria, and 
which constitute the material act of fecundation. The 
psychical manifestations which we have just noted 
and which so strikingly resemble the manifestations 
accompanying the copulative act in higher animals, ° 
are of themselves sufficient evidence ‘that this conju- 
gation is a sexual union. 


* Arch. de Zodlog. expérimentale, Vol. V, 1876. 
+ Fournal de Micrographie, 1882, p. 241. 


OF MICRO-ORGANISMS. 71 


The material changes effected inside the bodies of 
Infusoria in copulation do not extend to all their or- 
gans; the main mass of the body, the protoplasm, plays 
but a secondary vé/e in the matter; the change appears 
to be effected exclusively in the nucleus and the nu- 
cleole. 

Let us further state that, so far as is known, these 
changes are never effected apart from coition and be- 
fore the Infusoria actually embrace; copulation sets 
in every time, apparently, that these animals, under 
particularly favorable conditions, have actively repro- 
duced by fission. Fissiparity is then seen to cease 
and conjugation appears. 

We have not the time to sketch the history of this 
important question of physiology, interesting as it may 
be. It will be enough to recapitulate what we actu- 
ally know upon the subject, taking as our guide sub- 
stantially the views of M. Balbiani who, as is known, 
was the first scientist to study the physical phenome- 
na connected with fecundation among Infusoria. The 
divergencies between his observations and those of an- 
other eminent investigator, M. Biitschli, extend in re- 
ality only to points of detail. 

Let us first mark the modifications that take place 
within the Chzlodon cucudlus during conjugation. Each 
of the two Infusoria in copulation possesses a nucleus 
(endoplast, main nucleus) and, close beside this nu- 
cleus, an organ considerably smaller, a nucleole, or 
attendant nucleus, or latent nucleus (endoplastule, 
accessory nucleus); this minute body must not be mis- 
taken_ for the nucleole that is often found in the inte- 
rior of the nucleus among many Micro-organisms and 
in cellules; it has a function entirely different. 

Of these two elements, the nucleus plays an al- 


72 THE PSYCH CLLEE 


-~ 


most negative part in the act of fecundation. It as- 
sumes irregular outlines and becomes rumpled, while 
its contents collect in detached masses of various sizes: 
it grows clear by degrees and is finally absorbed. It 
disappears, accordingly, by a phenomenon of regres- 
sion and without dividing. 

Fecundation aims to replace this wasted element 
by a nucleus of fresh formation. The latter is pro- 
duced at the cost of the little body we have described 
by the name of attendant nucleus or latent nucleus. 
The attendant nucleus does not act in making upa 
main nucleus in the cellule of which it is a part; it 
finds its way into the body of the other animal and it 
is in this new cellule that it is destined to perform the 
function of a nucleus. 

In the Chilodon cucullulus, the attendant nucleus 
divides into two striated capsules, never more. These 
two capsules grow to unequal sizes; the largest attains 
a size of forty thousandths of a millimetre; it is this 
one that forms the new nucleus of the Chilodon. The 
second capsule shrinks and becomes compressed; it 
takes its place beside the first one and constitutes the 
new attendant nucleus. 

To the study of this type of fecundation we may 
limit our attention; it is the simplest of all, and other 
forms may be comprebended within it without much 
difficulty. What complicates the process in the other 
species is principally the successive modifications 
through which the old nucleus passes before suffering 
absorption. In the Stentor ceruleusthe nucleus has 
the shape of a long chaplet or string of beads; at the 
moment of fecundation the beads of the chaplet break 
apart and spread in the protoplasm where they finally 
become absorbéd. Among the Paramecia the phe- 


OF MICRO-ORGANISMS. 73 


nomenon is still different: the nucleus, at first massed 
together in a cluster, lengthens out into a very long 
string, which breaks; and the pieces becoming scat- 
tered about in the protoplasm, are absorbed. 

We find that fecundation in every instance intro- 
duces the dispersion and disappearance of the old nu- | 
_ cleus and that the latter is replaced by a new nucleus 
resulting from the transformation of the attendant nu- 
cleus that proceeded from the other organism. 

The various modifications presented by this atten- 
dant nucleus likewise contribute in great measure to 
the complexity of the phenomenon. We have seen 
that in the Chilodon the attendant nucleus breaks into 
two globules, of which one goes to form the new nu- 
cleus and the other the new attendant nucleus. Mat- 
ters take a different course in the Paramecia. In the 
Paramecium bursaria, for instance, the attendant nu- 
cleus divides into two and then into four capsules; 
one of these capsules suffers absorption, a second one 

becomes the attendant nucleus, and the two others 
coalesce with what remains of the old nucleus to form 
the nucleus proper. In the Paramecium aurelia the di- 
vision is made into eight capsules; three are cast out, 
and of the five left four are meant to form the new 
main nucleus; in reality, each Paramecium segmen- 
tates first into two and then into four divisions, and 
each of these four individuals takes one of the capsules. 
The fifth capsule is designed to form the attendant 
nucleuses of these four organisms; it divides, accord- 
ingly, into two and then into four parts; that is to say, 
into as many parts as the body of the animal divided, 

There is no question in our mind but that conjuga- 
tion in this case is a sexual phenomenon. A circum- 
stance that at the outset confirms this is the peculiar 


» 


— 


74 THE PSYGHLGCLT LL 


manceuvering the animalcula go through before aban- 
doning themselves to copulation; the movements they 
execute admit of exact comparison with the actions 
attendant upon copulation among higher animals. But 
we shall recur further on to the physiological signifi- 
cance of conjugation, when we shall endeavor to ex- 
plain, according to the most recent investigations, the 
function of the nucleus in the cellule. | 

The question may be asked, what is the starting- 
point, the provocative of these sexual phenomena, the 
cause that sets them inplay. Btitschli justly thinks, 
that conjugation is determined by internal causes; in 
fact, it takes place directly after very active periods of 
spontaneous division, as Balbiani has shown. When 
we bear in mind that the object of conjugation is to 
replace the old nucleus which has become wasted and 
worn out, we may conjecture with some degree of like- 
lihood that the physiological condition of the nucleus 
constitutes the sexual excitant that causes the Infuso- 
ria to copulate. 

However that may be, a curious observation witn 
the Paramecium aurelia has made us acquainted with 
one of the structural conditions of the sexual instinct 
in that Infusory. Fora long time J. Miller had pointed 
to the presence of filaments in the nucleus and even 
nucleolus of Paramecia, that had the appearance of 
spermatozoids. Observations to the same effect have 
increased since then, and it is now known that the 
filaments are Schizomycetes, parasitic Bacilli, which 
find their way into the nucleus and nucleolus, and mul- 
tiply, after their customary mode of segmentation, by 
disarticulation. Balbiani has definitely determined 
the nature of these filaments by morphological and 
micro-chemical methods; he has found out, among 


‘OF MICRO-ORGANISMS. 75 


other things, that the filaments do not dissolve in 
strongly concentrated alkaline solutions; and it is 
known that Bacteria exhibit this peculiar attribute of 
offering a great resistance to destructive agents. 


In the nucleus which they have penetrated, these 
parasites induce a pathological condition that results 
in destroying every manifestation of the sexual in- 
stinct in this Infusory. Among a swarm of animals of 
this species that are in copulation, single individuals 
are found that show a nucleus and nucleolus com- 
completely charged with Bacteria; sometimes these 
organs suffer an enormous dilatation, the nucleus be- 
coming nothing more than an enveloping membrane 
which is filled like a huge pouch with parasites. The 
animal continues to live, but it no longer attempts to 
copulate. 


VII. 


It is not our intention to make a full and complete 
study of fecundation in higher animals and plants; 
there is but one phase of that phenomenon that can 
enter into a general study of Micro-organisms, and that 
is the history of the sexual elements, of their form, 
their movements, and lastly their copulation. 


We shall describe animal fecundation first, and 
plant fecundation afterwards; regarding these phe- 
nomena particularly from a psychological standpoint. 


Among metazoans, fecundation may be divided 
into two distinct acts. The first, and most apparent, 
consists of the union of the two individuals; of this we 
shall not have to speak here; it is a phenomenon that 
lies outside the limits of our investigations. The sec- 
ond, more deep-seated, consists in the phenomena 


76 PHEOIPSY CHIC LLIFL 


that take place, after copulation, between the sperma- 
tozoid and the ovule. 

There are numerous reasons for comprehending a 
study of the generative elements within a general in- 
vestigation into the nature of Micro-organisms. 

In the very first place, it must be taken into ac- 
count, that these two elements are represented in ani- 
mals by a single cell. 

The ovule appears as a minute microscopic sphere 
enclosed by an envelope (vitelline membrane); it is 
formed of a mass of granulous protoplasm (vitellus) 
containing a nucleus (germinative vesicle) and one-or 
many nucleoli (germinative spot). The spermatozoids, 
in vertebrates, have quite a different aspect: they are 
filaments of varying lengths, having a distended part, 
or head, and a tapering, attenuated part, or tail. 

The resemblance that spermatozoids bear to Pro- 
tista, at first caused them to be regarded as animals 
living a parasitic life in the spermatic fluid. Ehren- 
berg classed them among the polygastric Infusoria. 
Keelliker and Lallemand were the first to reject this 
notion and the first to regard spermatozoids as ele- 
mental parts of living tissues, having the morpho- 
logical value of a cellule. They are now likened to de- 
tached cellular elements, such as blood-globules. 

Whatever form they assume, the sexual elements 
live as minute organisms independent of the individ- 
ual from which they originated. This circumstance is 
particularly remarkable in thecase of the male element, 
the spermatozoid, which retains its vitality for a cer- 
tain space of time after its expulsion. The length of 
this period varies with the different species. Whereas 
the spermatozoids thrown from a trout loseall motion 
in the water after the expiration of a few seconds, . 


OF MICRO-ORGANISMS. 97 


those of the bee, in the seminal reservoir of the fe- 
male, remain alive for several years. The seminal ele- 
ments of mammifers live for quite some time in the 
genital passages of the female. Balbiani has found 
living spermatozoids in the ducts of a she-rabbit twenty 
hours after coition. Ed. van Beneden, Benecke, Eimer, 
Fries, have observed that the sperm retains its prop- 
erties in the uterus of bats for several months. 

Another remarkable circumstance is, that the cop- 
ulation of the two sexual elements is not without anal- 
ogy to the copulation of the two animals from which 
they originated. The spermatozoid and the ovule, to 
some extent, repeat on a small scale what the two in- 
dividuals perform in their larger sphere. Thus, it is 
the spermatozoid that, in its capacity of male element, 
.~goes in quest of the female. It possesses, in view of 
the journeys it has to make, organs of locomotion that 
are lacking in the female and are useless to it. The 
spermatozoid of man and of a great number of mam- 
mifers is equipped with a long tail, the end of which 
describes a circular conical movement, which together 
with its rotation about its axis, determines the forward 
motion of the spermatozoid. The same mode of pro- 
gression is seen in the zodspores of Algz and in Masti- 
gophores, which are armed with flagella; the move- 
ments of the spermatozoid have been not improperly 
compared to those of a Flagellate. 

Other spermatozoids like those of the Triton and 
Axolotl are provided with a different kind of locomo 
tive apparatus; it consists of an undulatory membrane 
that acts like a real fin; the spermatozoid moves for- 
ward without turning about on its axis. 

There has been much discussion as to the nature 
of the forces that account for the movements of the 


78 TILE EOS VC LLC Le] Lee 


fecundative elements. The early investigators that 
concerned themselves with the study of animalcula, 
naturally attributed to them spontaneous and volun- 
tary movement. Since the spermatozoid has been re- 
garded as nothing else than an histological element, 
endosmotic, hygroscopic and like actions have been 
accepted in explanation. M. Balbiani, from whom we 
have taken the foregoing details, declares that expla- 
nations of this character are none at all; for, upon ul- 
timate analysis, all kinds of motion may be reduced 
to a chemical or physical action—sarcodic or ciliary 
movement just as much as voluntary movement. ‘“ For 
my part,” our scientist adds, “I believe that the sper- 
matozoids do not move about blindly but that they 
act in obedience to a kind of internal impulsion, to a 
sort of volition which directs them towards a definite 
object.”’* The experiments of M. Balbiani have shown 
that with weak solutions of ether and chloroform the 
movements of the spermatozoids may be moder td 
and made to cease so slowly that the latter ai ;et-ahie ° 
to fecundate the ovules. 2 







In fine, the spermatic element, ? gigiog itself 
toward the ovule to be fecundated, 1: ws y thes 
same sexual instinct that gies the’ @"rentrs ism 


towards its female. | 

In the higher animals, the movements of the 
spermatozoid that is endeavoring to reach the fe- 
male exhibit a peculiar character, which it is im- 
portant to emphasize: these movements do not ap- 
pear to be directly provoked by an exterior object, as 
those of micro-organisms are; the spermatozoid en- 
deavors to reach an ovule which is frequently situated 
a great distance away; this is the case particularly 


* La Génération des Vertébrés, p. 159. 


~ 


OF MICRO-ORGANISMS. 79 


with animals that fecundate internally, with birds and 
mammifers. The place of fecundation is still imper- 
fectly known. Coste at one time accepted the theory 
that the spermatozoid and ovule met in the ovary. 
Fecundation probably takes place in the fore part of 
the oviduct. It has little to do with our purpose, how- 
ever, to solve this delicate question precisely. A fact 
that is important to mention in a genera] way is the 
length of road the spermatozoid has to traverse before 
coming up with the ovule. 

Let us now follow the spermatozoid in its journey 
-to the ovule. It is known that the road it has to tra- 
verse 1s, in certain instances, extremely long. Thus, 
in the hen the oviduct measures 60 centimeters, and 
in large mammifers the passages have a length of 
from 25 to 30 centimeters. We might ask ourselves 
how such frail and minute creatures come by a power 
of locomotion great enough to enable them to traverse 
.so long a path. But observation discloses the fact 
that traoy are able to overcome obstacles quite out of 


proportic their size. Henle has seen spermato- 
Zoids Gf 5: g with them masses of crystals ten 
timesn of ti. 1 themselves, without appreciably les- 


selysion-neir ,.,eed. F. A. Pouchet has seen them 
carry bunches of from eight to ten blood-globules. M. 
Balbiani has attested the same fact. These globules, 
which have fastened themselves about the head of the 
spermatozoid, have each a volume double that of the 
head. Now, according to Welcker, the weight of a 
globule of human blood is 0.00008 of a milligramme: 
allowing that the spermatozoid has the same weight, 
we may then say that it is able to carry burdens four 
or five times heavier than itself. | 

The length of road traversed is not the only remark- 


80 LHL PD SVGHIC SLILE 


able circumstance here; there are also involutions and 
intricacies in the path to be followed in reaching the 
ovule. In this connection an interesting observation 
has been made upon the silk-worm. “ At the moment 
of conjugation the male deposits its seminal fluid in a 
special sac, the copulatory sac. The day following, 
this sac, which was distended by the sperm, is com- 
pletely flaccid, and nearly all the spermatozoids have 
traveled out into another sac, which opens into the 
oviduct opposite the first one, and there they wait to 
fecundate the ovules as they pass by. Now, the walls 
of the copulatory sac have no contractile power, and 
the passage of the spermatozoids from one sac into 
the other can be attributed only to a spontaneous 
movement. Further, a fact that well seems to verify 
this, is, that there still remains in the copulatory sac. 
a few misformed seminal elements, deprived of the 
power of locomotion.” * 

Let us now note what happens at the moment 
when spermatozoid and ovule come in contact with 
one another. The successive phenomena then taking 
place have been carefully studied by Fol in his work 
upon the star-fish (4sterias glactalis). The ovule has 
no enveloping membrane; it it is covered about only 
by a mucous layer, soft and flaky. The spermatozoids 
come up in great numbers and push forward into this 
layer; at this point they are all brought to a halt and 
become entangled among each other with the excep- 
tion of one, which, more speedy in its movements, out- 
strips the others and arrives within a short distance of 
the surface of the vitellus (or protoplasm of the ovule). 
At that moment, and before any contact whatever, there 
results a curious phenomenon of attraction between the 


* Balbiani, Comptes Rendus del’ Acad. des Sciences, 1869. 


OF MICRO-ORGANISMS. 81 


ovule and the spermatozoid; the peripheral substance 
of the ovule is seen to lift itself up in front of the sper- 
matazoid in the shape of a minute protuberance; this 
protuberance, at first, has a rounded shape, then it 
grows thinner and forms a point which advances to- 
wards the spermatozoid; this point is called the cone 
of attraction (see Fig. 8). The head of 
the spermatozoid fastens itself upon the 
cone, which seems to draw it into its in- 
terior. The tail of the spermatozoid does 
not appear to enter into the interior of 

v3, the ovule and take part in the process of 

Tebola ge fecundation, which consists simply in the 
Fig. §—A small fusion of the head of the spermatozoid 
portionoftheovule , 
of a star-fish (As¢e- With the nucleus of the cellule. 

Posting tis fone. As soon as the head of the spermato- 
tion of the cone of : : 
attraction. (Ac- Zoid has penetrated into the ovule, the 
cording to Fol.) : 4 

latter enwraps itself in an envelope, to 
protect itself against the other male elements. It ap- 
pears, in fact, to be well settled that the penetration 
into the vitellus of several spermatozoids marks the 
beginning of an adverse change: the subsequent seg- 
mentation of the ovule is irregular, and development 
ceases. 

The membrane in which the fecundated ovule of 
the Asterias glacialis infolds itself, is formed bya con- 
densation of the peripheral layer of the vitellus; the 
condensation starts from about the point where the 
Spermatozoid penetrated, and gradually spreads over 
’ the whole surface of the ovule; the formation of this 
. protective membrane is so rapidly effected, that access 
to the ovule is barred against spermatozoids who might 
be only a few seconds behind the first one. 

Sexual selection, then, acts among spermatozoids 





0. 
se PR a 


er 
* a.0°e 9 
C 

eee ANI 
. * es 


82 TALE SE SY CLL Ce LILLE 


just as among all animals; it is the most agile and 
the stoutest spermatozoid that first penetrates the ovule 
and effects fecundation. The laws of selection, thor- 
oughly developed by Darwin, do not only apply to in- 
dividuals; they apply also to sexual elements. 

We are unable to follow the successive modifica- 
tions suffered by the head of the spermatozoid after 
its entrance into the ovule; we may state simply, that 
the head presents the appearance of a radiate figure, 
of a diminutive sun advancing towards the female nu- 
cleus. At the same moment, the female nucleus ap- 
pears affected and puts itself in motion towards the 
spermatic nucleus. The two nuclei soon come almost 
within contact, and it is in particular the female nu- 
cleus that then plays the active part. It is disturbed. 
by incessant movements and every moment changes 
its form; it thrusts out prolongations towards the male 
nucleus, and one of these prolongations fastens itself 
upon the latter, presenting at the end a minute de- 
pression in the shape of a cup, which receives the male 
nucleus; and the two nuclei, while executing active 
movements, fuse into one another. In this manner 
the first nucleus of segmentation is created. 

Selenka has furnished interesting chronological | 
data as to the time of appearance of the different phe- 
nomena. The time is in each case taken from the mo- 
ment of artificial fecundation. After a lapse of five 
minutes, the spermatozoid has forced an entrance into 
the ovule.* At the expiration of ten minutes (that is, 
five minutes after entrance), it has reached the centre 
of the ovule. At twelve minutes, the female nucleus - 
has put itself in motion to meet the spermatic nucle- 


*M. Balbiani, Cours sur la fécondation, passim. Y¥ournal de Micrographie 
Vol. III. 1879. 


OF MICRO-ORGANISMS. 83 


us. Finally, at the twentieth minute, the two nuclei 
have united. 

In the psychical history of animal fecundation as 
just given, there are many gaps: the history of vege- 
table fecundation will fill several of these. 

The simplest forms of sexual reproduction in veg- 
etables are those where the male and female cellules 
are quite the same and advance to meet each other 
equally; thus possessing not only the same form, but 
also the same properties. In a small Alga bearing the 
name of Vlothrix serrata, the interior of certain cellules 
divides into two parts, which separate, then come to- 
gether again and mingle anew into a minute mass 
which, when set at liberty, reproduces the plant entire. 
In other species the inside divides into small naked 
cellules, which are first set at lhberty and for some 
time move briskly about in the water by means of cilia 
with which they are provided, before fusing into one 
another. These cellules are called zodspores. The 
_differentiation is further marked in certain species, the 
zoospores of which have neither the same farm nor the 
same properties. Some leave their positions to go to 
meet the others: these are the male cellules, the an- 
therozoids; others make no movement at all and limit 
their ~dé/e to that of waiting: these are the zodspores. 
Similarly, in an Alga bearing the name of Spheroplea 
annulina, there are found two kinds of filaments, 
brown and green. In the green filaments the proto- 
plasm of certain cellules breaks up into a definite num- 
ber of ovoid bodies which remain immobile; in the in- 
terim, the cellules of the brown filaments liberate mo- 
bile spores provided with two flagella: these spores, 
veritable male cellules, ply briskly about in the water 
and then proceed to fix themselves to the green fila- 


84 THE PSV CHLOALIFLE 


ments, the cellules of which are pierced by pores; 
through these orifices they penetrate into the cellules 
and fuse with the immobile ovoid bodies, which are 
nothing else than zodspores. ; 

The psychical phenomena attending this mode of 
conjugation may be still more complicated, as shown 
by the observation that Berthold has made upon the 
conjugation of the zodéspores of the Lctocarpus silicu- 
losus. The Ectocarpus belongs toa group of algz char- 
acterized by the presence of mobile spores which re- 
produce the plant. These zodspores are little pear- 
shaped cellules, of which the tapering end 1s colorless, 
and the rounded end shows a brownish-green colora- 
tion, which is due to the presence of an extensive 
chromatophore; at the edge of the chromatophore a 
deep depression is sharply marked, which appears to 
be aneye. Every zoéspore is equipped, in addition, 
with two flagella, which rise from the same point of 
the lateral skirt of the anterior extremity of the body; 
one of these flagella points forwards and the other 
backwards. When the zodspores are 
set at liberty and begin to swim about 


unnoticed. The female cellule does 
not draw about her the male cellules, 
from which, moreover, it differs by no 


Fig. 9. —Sexual ree morphological mark. But at a given 
production of the £cfo- 


carpus siliculosus. Dif- moment the female zodspore becomes 
ferent stages of the fe- 


male zodspore while distinguished from the male cellules 
entering the state of 


rest (after Berthold). by passing into astate of rest; where- 
to, the base of the anterior flagellum, which is laterally 





, in the water, they pass each other by 
é 


inserted, proceeds to blend with the anterior part of — 


the body with the effect that the flagellum appears to 
rise from the extremity; during the same time, it 


OF MICRO-ORGANISMS. 85 


contracts, and presents at its free end a slight pro- 
tuberance, which allows the zoéspore to fix itself upon 
an immobile point; as to the rear flagellum, it slips 
back upon the posterior part of the body which it 
encompasses, and finally disappears.—When the fe- 
male zodspore has become motionless, the male zo6- 
spores, hitherto indifferent, are seen to make towards 
it and to surround it ina half-circle; the number of 
zoospores that thus meet, is quite considerable; it 
frequently exceeds a hundred 
(fig. 10). They let their second 
flagellum float loosely behind 
them, while they all direct their 
anterior filament towards the fe- 
male cellule; this filament they 
draw back and forth over the 
Fig. ro. —Sexual reproduc. body of the female cellule; they 

ee reg Cr ee perform upon it real acts of feel- 
rounded by male zobspores. ing the object of which is evi- 
dently to provoke in the female zodspore a genital ex- 
citation, as what follows will prove. It happens at 
times that several of the male zodspores quit the 
ranks and make off; they are immediately replaced by 
others who employ 

their filaments in a 

—m  Ukemanner,tostroke 
6:9) the female. Finally, 
upon the expiration 

of a certain time, 








Fig, rr. — Sexual reproduction of the Zcto- ONC of the zoospores 
carpus stliculosus. Successive stages of the 1 h half-ci 
copulation of a female zoéspore with one of the 1€AVES the hali-cir- 

] 6 ; 
“a aight cle and approaches 
the female. The two zodspores unite; after having 


presented the series of changes marked in the figure,— 


86 HE IPSUCH LEC Leis 


when the fusion is complete,—the female cellule loses 
its fixatory filament and the little zygote, the result of 
the fusion, is set free. 

When the male zoéspore is obliged to go a long 
distance to reach the female zodspore, it has been 
thought that the latter secretes a substance which acts 
upon the male cellule as a chemical excitant and 
which marks out for him the direction to follow. The 
supposition is quite probable; it was suggested by 
Strasburger, who had shown that the spermatozoids 
of the Marchantia polymorpha are attracted by the 
substance that issues from the archegonium. It will 
only be necessary to assist at an experiment of artifi- 
cial fecundation with fish-spawn, in order to come to 
the same opinion. The sperm introduced into the 
liquid preparation does not spread about homogene- 
ously in all directions; the spermatozoids are observed 
-to whirl about the ovules in great masses; it must be 
supposed, further, that there is some excitation of an 
unknown nature which attracts the spermatozoid to- 
wards the micropyle, for this minute opening, of which 
the diameter is scarcely that of the head of a sperma- 
tozoid, is the only orifice through which the male ele- 
ment can enter into the ovule to fecundate it. 

These ingenious opinions have been latterly con- 
firmed by the very interesting experiments of M. 
Pfeffer, professor at the University of Tiibingen, upon 3 
the movements of spermatozoids.* His investigations 
had to do principally with the spermatozoids of cryp- 
tograms. M. Pfeffer discovered that certain chemical 
substances have the property of attracting these sper- 
matozoids. 


* Pfeffer, Untersuchungen aus dent botanischen Institut zu Tibingen, 
Vol. I. Leipzig, 1884, p. 363. 


OF MICRO-ORGANISMS. 87 


The manner of conducting the experiment is as 
follows. A solution of the substance to be experi- 
mented upon is placed in small capillary tubes with a 
light-aperture of from five to seven hundredths of a 
millimeter wide. These capillary tubes dip into a 
watch-crystal covered with a liquid, wherein quantities 
of spermatozoids have been placed. Under these cir- 
cumstances currents of diffusion are soon set up be- 
tween the tube and the liquid in the watch-crystal, 
and when the substance experimented upon is’ the 
proper one, the spermatozoids are seen to follow the 
currents of diffusion and to penetrate into the tube. 

The substance exerting such attraction varies 
with the plants. The author began by experimenting 
upon the spermatozoids of certain ferns (Adiantum 
cuneatum). After a great many fruitless trials, one 
substance, and one only, proved to be effective: 
namely, a solution of malic acid or malate. It is to be 
presumed, then, that, in the organic kingdom, malic 
acid must be the substance acting as a chemical ex- 
citation upon the spermatozoids of ferns and guiding 
them towards the female cellule. 

According to the hypothesis of Pfeffer, the actual 
process takes place in the following manner. The 
spore of a fern, falling upon humid ground, germinates 
and gives birth to a green cordate slip, the prothat- 
lium, upon which are developed the male organs or 
anthertdia, and the female organs or archegonia. At — 
a certain moment, elongate cellules, spirally twisted 
and extremely mobile, issue from the antheridium: 
these are the spermatozoids. They are equipped with 
vibratile cilia, by the help of which they are able to 
start in search of the female cellule. At the same in- 
stant, the female organ, the archegonium, opens and 


88 THE? PSYCHIC TILL 


emits a mucilaginous substance, which must contain 
malic acid or a malate, for these compounds are the 
particular excitatory substance of the fern-spermato- 
zoids. Thanks to a drop of dew that falls upon the 
prothallium, the spermatozoids swim around and ap- 
proach the female ovule, which attracts them by acting 
upon them with the malic acid. 

A confirmation of this hypothesis is primarily the 
fact, that all substances tested, with the exception of 
malic acid and malates, remained completely inactive; 
another proof is, that malic acid is found in prothal- 
lium-decoctions of the Preris serrudata and of the Ad- 
zantum capillus veneris; another proof still, is the cir- 
cumstance that malic acid is largely diffused through- 
out the vegetable kingdom. 

The author has made, in this connection, a series 
of very curious experiments upon the degree of con- 
centration necessary to attract the spermatozoids. 
The lower limit at which attraction begins, is found in 
a solution containing malic acid in the proportion of 
one to 1000 parts. This the author has designated 
by a favorite word of the Germans: ezz-Schwelle, or, 
in other words, the threshold of excitation. 

When the solution in the watch-crystal contains 
one part malic acid to every thousand parts, in order to 
make the spermatozoids pass from the watch-crystal 
into the tube, the solution held in the tube must be 
thirty times as strong, or 30 x I-1000 = 3-100. Ifthe 
liquid in the watch-crystal contains one part malic 
acid to every hundred parts, similarly the solution of 
the tube must be thirty times as strong, that is to say 
three tenths. : 

The author justly compares the result of these ex- 
periments with the law laid down by Weber, which M. 


Of MICRO-ORGANISMS. 89 


Delbceuf has happily formulated as follows: “The 
slightest difference capable of being felt between two 
excitations of the same sort is due to an actual differ- 
ence that increases proportionally with the excitations 
themselves.” Thus, in order to tell that one weight is 
heavier than another, it must be heavier than the 
other by a fractional difference which varies from one 
third to one fifth according to the individual, be the 
original weight what it may. For example, to a weight 
of three grammes, in order that a difference may be 
made perceptible, we must add one third of three 
grammes orone gramme. To four grammes we must 
add one third of four grammes, or one and one third 
grammes, etc.* 

_ According to Pfeffer, the application of Weber’s law 
to his experiments is so exact that, when the solution 
of the tube is only twenty times stronger than that of 
the watch-crystal, the spermatozoids remain unaf- 
fected. Furthermore, the application of the law is not 
disturbed by changes of temperature varying within 
certain limits. Thus, down to a temperature of + 5° 
(41° Fahr.) the spermatozoids remain sensible to a 
concentration of liquid thirty times as strong as that 
in which they are. 

Basing his calculations upon these experiments, 
the author has succeeded in determining the probable 
quantity of malic acid that must be contained in the 
archegonium. This quantity is probably in the pro- 
portion of three tenths. 

The spermatozoids of the Se/aginella are likewise 
wise attracted by malic acid and the malates. As re- 
gards the Marciliacee, the specific substance has not 
been discovered. The same failure, also, in the case 


* Consult Ribot, Psychologie allemande, p. 161. 


ca 


go + EL OPS V CPL ee barre | ; 
of the Hepatice. The author concludes from this, 
that the substance operating in these two cases can be 
little diffused throughout the vegetable kingdom. 

For the spermatozoids of the /unarita hygrometrica 
(Conferve), the operative substance 1s cane-sugar. 
No other attracts them. The spermatozoids remain 
unaffected even by substances bearing the closest anal- 
ogies with cane-sugar. We will cite, by way of ex- 
ample, fruit-sugar or levulose, grape-sugar or glucose, 
glycogen, manna, milk-sugar, etc.; these substances 
exert no attraction upon the movements of the sper- 
matozoids, whereas cane-sugar exercises an attraction 
so powerful that the capillary tube becomes at once 
crammed with them. The excitation first induces in 
the spermatozoid a movement of direction: the body 
is brought into a position enabling it to reach the tube 
by movement in a straight line. The same phenome- 
non has been observed by Strasburger in the case of 
Algze zodspores; when these minute beings are at- 
tracted by a chemical or luminous excitation, the first 
thing that happens is the directing of the body 
towards the attracting source. 

A solution of one in one thousand parts is suffi- | 
ciently concentrated to draw the spermatozoids of 
Mosses into the capillary tubes.. The “threshold of 
excitation”? for them, accordingly, is» the same as for 
the spermatozoids of ferns. Furthermore, Weber’s 
law is in this instance again verified; only, in order to 
have the chemical excitation produce a different at- 
traction, it must be stronger than the first in the pro- 
portion of 50 to 100. In the experiments upon the 
spermatozoids of ferns the ratio is a little smaller; be- 
ing only 30 to 100. 

The question presented itself to the author as to 


OF MICRO-ORGANISMS. gi 


whether, by increasing the degree of concentration, a 
point would not be reached where attraction would 
change to repulsion; he has not made the experiment, 
but he has noticed that great numbers of spermato- 
zoids still penetrate into the tube when contain- 
ing a solution in the proportion of 15 to 100, not- 
withstanding the fact that they there meet a speedy 
death. 

The general conclusion to be derived from these 
numerous experiments is, first, that the spermatozoids 
are sensible to certain chemical excitations, and conse- 
quently, that in every group of plants there exists a 
special substance acting the part of a specific excitant 
towards the spermatozoids. The author does not hes- 
itate to regard the spermatozoids as a physiological 
re-agent of such substances, allowing feeble traces of 
the same to be detected in a liquid solution. He thus 
comes to form a sfermatozotd test, which is not with- 
out analogy with the Bacteria test, invented by En- 
gelmann. An application of the test is the following: 
a decoction of herbs having presented the property of 
attracting the spermatozoids of Mosses, the author 
concluded that the decoction must contain cane- 
sugar. 


Vill. 
THE PHYSIOLOGICAL FUNCTION OF THE NUCLEUS. 


It would be of the highest importance to know 
what is the seat of the phenomena of the life of re- 
lation in the bodies of Micro-organisms. We have 
seen that Micro-organisms are the equivalent of a 
simple cellule, composed, according to the classic 
plan, of a protoplasm, of a cellular nucleus, and of an 
enveloping membrane. 


92 LAE PSVCHLOC LATE 


Each of these elements plays a part of special im- 
portance in the vital phenomena of these beings. 
Long since, scientists have attributed movement, 
sensibility, and the prehension of foods, to the proto- 
plasm. This was the result of direct observation. While 
observing an Amceba, for example, the protoplasm is 
seen to undergo modifications of form and to throw 
out pseudopods, either for the purpose of effecting a 
change of position, or to seize alimentary substances. 
The protoplasm, accordingly, seems to be the sole 
agent of all these phenomena. Likewise, the vibratile 
cilia of the Ciliates, which are at once organs of mo- 
tion, prehension, and touch; the suckers of the Acin- 
etinide, which are special organs of prehension, are 
nothing else than outward expansions of the proto- 
plasm proper. 

As regards the enveloping membrane, the same 
cannot discharge any psychical function: firstly, be- 
cause it is a product of protoplasmic secretion; and, 
secondly, because it is wanting in many Protozoans 
and even in many animalcula quite high in point of 
organization that, despite their nudity, exhibit marks 
of psychic life just as complex as those observed in 
Infusoria having a cuticle. The part acted by the nu- 
cleus does not so clearly manifest itself to direct ob- 
servation; it executes no movements in the ordinary 
conditions of life; it remains motionless in the centre 
of the animal’s body, surrounded on all sides by the 
protoplasm; unlike the latter, it is not in direct con- 
tact with the outside world. 

The first phenomena that have enabled us to con- 
jecture as to the significance of the nucleus, have to do 
with the division of cellules; when a cellule divides, 
the nucleus comes into action, it exhibits certain 


OF MICRO-ORGANISMS. 93 


movements, and passes through complicated stages 
which have been given the name of caryokinesis.* 

But these complex phenomena simply show the 
function of the nucleus as an histological element; 
they do not afford any disclosures as to the physiolog- 
ical vd/e of the nucleus in the cellule. 

Other observations have enabled naturalists to sur- 
mise what phenomena are subject to the action of the 
nucleus. In 1881, Balbiani called attention to indi- 
viduals, belonging to the species Paramecium aurelia, 
that were destitute of a nucleus and which neverthe- 
less possessed the power of locomotion the same as 
ordinary individuals; whence, he concluded that the 
nuclei exerted no influence upon the phenomena of 
individual life. Shortly afterwards, Gruber observed 
small specimens of the Actznophrys sol which absorbed 
nutriment, changed their position in the liquid, and 
even fused with each other (zygosis), but which were 
nevertheless destitute of a nucleus.} 

The idea then occurred to Gruber, and to Nuss- 
baum likewise, to divide the Micro-organisms by ar- 
tificial means into several fragments, of which some 
would contain a nucleus and others not, and then to 
watch what would come of it. Gruber, to whose ex- 
periments the most importance attaches, chose as his 
subject of trial the Stentor cwruleus, a ciliated Infu- 
sory of great size, which exhibits a nucleus resembling 
a chaplet of beads (moniliform). He afterwards con- 
tinued his experiments upon other species, and his 
conclusion was, that the power to regenerate lost parts 
belonged to all Protozoans, but that this phenomenon 
only took place when the isolated fragment contained 





* kdpvov, the nut, and Kivyoic, motion, disturbance. 
+ Contributions to the Bzologisches Centralblatt, 1885. p. 73. 


94 THE PSYCHLICALLFE 


some portion of the nucleus; in which case the animal 
reproduces all the organs it has lost in consequence 
of its dissection. Furthermore, the process of the for- 
mation is exactly the same as in the spontaneous di- 
vision of these same Infusoria. The excitation caused 
by their removal is accordingly of the same character 
as the unknown excitation that provokes the natural 
division of the body. 


From these experiments, the part acted by the nu- 
cleus is indicated by complete evidence. Gruber shows 
that in a single instance only can a fragment without 
a nucleus form itself anew; and that is, when the frag- 
ment contains an organ in course of formation, as hap- 
pens, for example, during the spontaneous division of 
the animal. This amounts to saying, that the presence 
of a nucleus is necessary to give the impulse to the 
formation of the organ, but that it is not necessary to 
the completion of the organ when the impulse has 
~once been given. 


Lastly, if the fragment is totally destitute of a nu- 
cleus, it does not re-form itself so as to constitute a 


complete animal again; if the fragment possesses nel- 


ther mouth nor peristome, it does not reproduce a 
new mouth and a new peristome;.yet the fragments 
continue to live and to move. The absence of a nu- 
cleus does not suspend the functions of motion, sensi- 
bility, nutrition, or growth. This conclusion is, in 


our estimation, too sweeping, as.we shall see fur-— 


ther on.* 
M. Balbiani has recently repeated these experi- 
ments of artificial division, and, while confirming in 


* We have taken as our guide, with the permission of M. Balbiani, the lec- 
tures delivered by that eminent authority at the Collége de France, in 
May, 1887. 


a 


ake 


OF MICRO-ORGANISMS. 95 


general the results of Gruber as to the function of the 
nucleus in the vital phenomena of ciliated Infusoria, 
he has endeavored to fix with more exactness a cer- 
tain number of important points. His first experi- 
ments, like those of Gruber, were conducted upon the 
Stentor ceruleus, a species of which the size renders it 
better adapted to this sort of experimenting. In an 
observation which we shall take as a type, and which 
is represented by the figure sent to us by M. Balbiani, 
the body of the Stentor is cut by two transverse sec- 
tions; three divisions are obtained, each of which con- 
tains a fragment of the nucleus. We will remember 
that the nucleus of the Stentor is like a long string of 
beads; it is not at all rare to see a fragment of a Sten- 
tor contain one or more beads. 









eo 


Fig, 72.—Artificial division of the Stextor ceruleus. 
(After Balbiani.) 





Let us follow the phenomena presented in the 
middle segment. This segment contains only a single 
grain of the nuclear chaplet; directly after severance, 
it assumed a globular shape; the day following, it had 
lengthened, had grown a tail at the posterior extrem- 
ity, and upon the anterior part there had appeared, 
distinctly outlined, a crown of cilia longer than those 
upon the body; in other words, a peristome had 


—_ 


gO. - THE OPSVCHIC (LIE 


formed; the day after, the fragment had increased 
considerably in bulk, and in two days more the ani- 
mal had formed a mouth. During this time, the nuclear 
grain had multiphed: five, in fact, were counted. The 
animal had the normal form; its size, however, was a 
little smaller than that of the ordinary Stentors. 
Thus, through the action of a small quantity of nu- 
clear substance, the fragment has been completely re- 
constructed. 

It frequently happens that the artificial severing of 
the animal causes various deformations in the frag- 
ments. The deformation disappears with the greatest 
rapidity in fragments containing nuclear substance. 
The wound heals instantly; directly after severance, 
the two edges of the wound are seen to adjust them- | 
selves to each other. 

In all these particulars, the experiments confirm 
the results obtained by Gruber. 

M. Balbiani desired to ascertain what would hap- 
pen if the division were made during the state of con- 
jugation. 

Conjugation, as we know, aims at replacing an old, 
spent element, that has lost its physiological proper- 
ties, by an element of new formation proceeding from 
an attendant nucleus (nucleolus) exchanged between 
the individuals in conjugation. The point in question 
was to ascertain whether the nucleus that was be- 
ginning to disappear, had lost its regenerative power. 
In the Stentors, during conjugation, this old nucleus 
breaks, and its nuclear globules are scattered to all 
parts of the protoplasm. When at this stage, the body 
of one of the Stentors is divided in such a manner that 
the fragment contains some of the scattered globules 
that came from the old nucleus. It is quite evident 


OF MICRO-ORGANISMS. 97 


that such a fragment is obtainable only by mere acci- 
dent. 

In an experiment which we again cite as a type of 
many others, the fragment containing the elements of 
the old nucleus tends to reconstruct itself; this frag- 
ment, which represented the posterior part of the 
animal, presented, the day following, a rudimentary 
peristome; the reconstruction did not go beyond this 
point: it was left incomplete. Accordingly, the old nu- 
cleus loses its power of regeneration. 

As to the phenomena presented in fragments con- 
taining no nuclear substance, M. Balbiani has made 
decided advances in the question; he hascompleted the 
experiments of Gruber, he has also corrected them, 
and he has reached conclusions essentially different. 

In order to understand more thoroughly the phe- 
nomena connected with the absence of nuclear sub- 
stance, the author has directed his attention to an- 
other species, the Cyrtostomum leucas, which has the 
advantage that it can be kept longer alive than the 
Stentor can, on a glass slide holding a drop of water. 
The Cyrtostomum is a large ciliated Infusory of more 
than four-tenths of a millimeter in length. Its proto- 
plasm is differentiated into two layers, one of which, 
the cortical, encloses very heavy trichocysts; the other, 
the endoplasm, holds alimentary substances. The an- 
imal exhibits upon one of its faces a mouth, shaped 
like a long narrow buttonhole, and upon the other 
face acontractile vesicle, from which crooked and an- 
astomosed passages radiate. It is easy, by making a 
transversal division, to obtain fragments without nu- 
clear matter; the nucleus of the Cyrtostomum being 
formed of a single, round mass. But it is not easy, on 
the other hand, to obtain fragments likely to live, 


98 THE PSYCHIC LIFE 


since this animalcule has a dense ectoplasm, and, 
when severed, this layer, which is not very retractile, 
does not grow together again and close the wound; 
the sides remain separated, the water comes in con- 
tact with the endoplasm, which swells, bulges out, and 
runs from the wound; the animal may thus void itself 
completely, dying of diffluence. It occasionally hap- 
pens that the animal voids itself only in part, and that 
the nucleus escapes with a small piece of the proto- 
plasm. Then, if the wound draws together, we get a 
fragment that has thrown out the nucleus by its own 
action. 

~ We shall not speak of the actions of the fragment 
containing nuclear substance; they are the same as 
observed in the case of Stentors: the fragment 
rapidly reconstructs itself and re-forms a complete 
animal. 

Let us mark more closely the fragment without nu- 
cleus. Such fragments continue to live for some 
time; they have been keptalive as long as eight days; 
but they do not reconstruct themselves; they do not 
even assume a regular form; the part of the body fac- 
ing the section retains its obliquity of truncation. At 
the start, for the first few days, the movements con- 
tinue; a curious circumstance connected therewith is, 
that the fragments continue to move in the direction 
in which they would have moved if they were placed 
together to form a complete individual.. The vibratile 
cilia are in no wise altered; they shake with the same 
animation as before. Only the movements of the an- 
imal are a trifle irregular; but they exhibit the same 
marks of volition as seen in normal individuals. The 
vesicle continues to contract. 

The power to seize food is also retained when the 


OF MICRO-ORGANISMS. 99 


fragment without nucleus contains the mouth; the 
mouth ingests alimentary substances. If the Cyrtosto- 
mum be given grains of potato fecula, which it is very 
partial to, the fragment without nucleus, but with a 
mouth, swallows these grains and fills itself with them. 
It is not known whether it digests them. 

This much was observed in the first stages, and 
Gruber was wrong in stopping at this point. 

At the expiration of a certain time, varying be- 
tween the third and fourth day, alterations of structure 
are noticed in the fragment that are probably traceable 
to the absence of the nucleus. One of the first to take 
place is the disappearance of the marks of ditferentia- 
tion which we have observed to distinguish the endo- 
plasm from the ectoplasm. The dark granules that 
fill the interior of the body congregate in the centre 
by abandoning the peripheral part; then these granules 
scatter and come toa position just beneath the cuticle, 
which denotes a deliquescence of the plasma. The 
layer of trichocysts undergoes changes and disap- 
pears. All these alterations result from an actual dis- 
organization of the plasma. The contractile vesicle 
shrinks, its pulsations decrease, the radiating passages 
disappear. The body of the animal, which in its nor- 
mal condition is elongate, becomes rounded; its move- 
ments flag and consist of nothing but a rotation of 
the body about its own axis; at last the animal be- 
comes motionless and dies of diffluence. 

These changes are not due to lack of sustenance, 
as one might suppose; for fragments that have a 
mouth and swallow food, pass through the same alter- 
ations as those that have no mouth.* 


* M. Balbiani has informed us, upon request, that the fragments of Cyr- 
tostomum furnished with nucleus can be kept alive for a much longer time 


100 THE. PSYCHIC LIFE: 


It is superfluous to insist upon the importance of 
these results, obtained by a method that might be 
called experimental physiology applied to unicellular 
organisms. Although the experiments have been 
made solely with ciliated Infusoria, the results of the 
same may be extended to all cellules, for the Infusoria 
are nothing more than autonomous cellules living an 
independent life. 

The conclusion from the above researches of M. 
Balbiani, which, as we have seen, go far beyond those 
of Gruber, is, that the nucleus is not necessary merely 
to the regeneration of the parts, as the German pro- 
fessor believed. The error made by Gruber arose 
from the fact that he did not follow the career of the 
fragments deprived of a nucleus long enough; if he 
had continued his observations, he would have seen 
that the fragment becomes gradually disorganized. 
The nucleus, according!y, has not merely a formative 
power; it does not merely regulate alimentation, re- — 
adjustment of form, and the healing of wounds; it has 
not merely a regenerative power, enabling the plasma 
to reconstruct complete the organs lost by artificial 
severance. The nucleus is, besides all this, an essen- 
tial factor of the plasm’s vitality. If a fragment of 
protoplasm be deprived of its nucleus, the fragment 
remains alive for some time, but afterwards under- 
goes disorganization. 

Such are the facts, extremely complex, and conse- 
quently difficult to summarize by a formulated state- 
ment. 





under the same conditions (that is, in a dropof water on a glass slide kept in 
the moist chamber of Malassez): in this way it is possible to keep them alive 
for the space of a month, by introducing into the liquid a few Infusoria to serve 
them as food. On the other hand, the fragments deprived of nucleus by sec- 
tion live for only eight days at the most. 


OF MICRO-ORGANISMS. IOI 


We certainly cannot regard the protoplasm as in- 
ert matter; but what appears. probable is, that the pro- 
toplasm receives from the nucleus the communication, 
- the delegation of physiological powers. The nucleus is 
in a certain sense the focal seat of life in all its forms. 

If we get rid of the nucleus by artificial section, 
the fragment of enucleated protoplasm continues to 
live for some time, having received from the nucleus 
an impulsion that has not yet been exhausted; but af- 
ter a certain length of time, the impulsion given by the 
nucleus not being renewed, the protoplasm runs its 
course and dies. 

From the psychical point of view, which more par- 
ticularly occupies our attention here, how are the re- 
sults of these experiments in cellular vivisection to be 
explained? When a fragment of an organism, deprived 
of nuclear substance, is seen to move about freely and 
with the same activity as if it still possessed its nu- 
cleus, we are constrained to admit that the phenom- 
ena of the life of relation, or movement and sen- 
sibility, have their seat in the protoplasm. But it is 
probable that such physiological capacities as the 
powers of nutritfon, are not inherent in protoplasm; 
they depend immediately upon the presence of the 
nucleus, for they disappear little by little and finally 
vanish a few days after the removal of the nucleus.* 

It may be mentioned in passing, that there are cer- 
tain psychical properties which the nucleus apparently 
does not transmit to the protoplasm, but which it re- 
tains for itself; this is the case with the instinct of gen- 


* The difficult question here, is to ascertain whether the psychical proper- 
ties of the protoplasm are destroyed through the direct effect of the disorgan- 
ization of the plasma, or whether they disappear a short time before the 
process of disorganization and in consequence of the absence of nuclear sub- 
stance. 


102 LLL ik SVGCHLG. Loy Lees 


eration. We have already seen that, during the epi- 
demic periods of conjugation, the Paramecia which 
have their nuclei overrun with parasites cease to con- 
jugate with animals of the same species. The destruc- 
tion of their nucleus by the Bacteria produces in the 
Paramecia the effect of actual castration. 

The removal of the nucleus, accordingly, causes 
the interruption of the following functions and in the 
following order as to time: 

1. The regenerative and reproductive property of 
the plasma; 

2. The vitality of the plasma, and the psychical 
functions. 

The psychologist will notice with interest that the 
psychical function of the protoplasm outlives the re- 
generative function for an appreciable length of time; 
a fragment of a cellule which, having been mutilated 
by the act of severance, is unable to correct its out- 
ward form, or to secrete a fresh cuticle, or to recon- 
struct its lost organs, is nevertheless still capable of 
perceiving sensations and of responding thereto by 
movements. Psychical life is consequently a prop- 
erty of living matter which appears to be less complex 
than the regenerative property, inasmuch as it ceases 
later. | 

To summarize, the nucleus plays the primordial 
vole in the cellule; if, to use an old comparison of Ar- 
istotle’s, we compare the protoplasm to the clay, we 
must compare the nucleus to the potter that fashions 
it. The nucleus comprehends all the physiological 
properties, the totality of which goes to constitute 
life. 

It is interesting to note what perfect accord pre- 
vails between these recently discovered facts and the 


OF MICRO-ORGANISMS. 103 


phenomena relative to fecundation. Fecundation con- 
sists in the fusion of two nuclei, of which one proceeds 
from the male, and one from the female. Thus, it is 
through the intermediary office of the nucleus that all 
the faculties, all the properties possessed by the par- 
ents,—the form of their bodies as well as their psychi- 
cal faculties,—are transmitted to the embryo; as we 
have just remarked, therefore, all these properties 
must be comprehended in the nucleus, in order to pass 
into the embryo. 

We must note further, that the embryo takes from 
the mother something besides the nucleus. While itis 
connected with the father through the head of the 
spermatozoid, which has the morphological value of a 
nucleus, it receives from the mother not only the fe- 
male nucleus but also the vitelline plasma of the 
ovule; now, as the embryo does not exhibit a greater 
morphological likeness to the mother than to the fa- 
ther, we may thence infer that the vitelline protoplasm 
inherited from the mother exerts no formative influ- 
ence upon the development of its body. 

These are not the only facts the connection of 
which we desire to show with the results of experi- 
ments upon the function of the nucleus. It will be well 
to point out here, how reproduction is effected among 
organisms which, besides their nucleus, possess other 
differentiated organs. The best known and perhaps 
the most general mode of reproduction 1s fissiparity, 
which consists in a division of the entire body into two 
equal parts. If we closely follow the course of this 
phenomenon in any organism whatever, we shall find 
that the division begins by a multiplication of the 
principal organs of the body. The nucleus begins by 
lengthening out and assuming a position perpendicu- 


~ 


104 THE PSYCHIC LIFE 


lar to the plane of division. The first organ that mul- 
tiplies is the flagellum; it does not split into two parts, 
as several English authors have supposed; according 
to the observations of Biitschli and of Klebs, a second 
flagellum is formed complete. The pigmentary spot 
also does not divide into two parts; the old eye re- 
mains by a sort of preference with one of the parts, 
while the other part acquires a new eye, formed com- - 
plete; this is likewise the case with the mouth and the 
cesophagus. There are only two elements that multi- 
ply by division: the chromatophores and the nucleus. 
Now, when we note that the chromatophores contain a 
body, the pyrenoid, which exhibits the closest analogy 
of chemical composition with the nucleus, we may 
properly say that the nuclear elements of the cellule 
are the only ones that do not reproduce by neoforma- 
tion at the expense of the protoplasm, as is the case 
with the cilia and the flagella. 

The reason for this mode of multiplication by nu- 
clear elements will be comprehended, if we consider 
the matter in the light of experiments made upon the 
formative properties of the nucleus. We have seen, 
in fact, that the nucleus can regenerate the protoplasm, 
but that the protoplasm cannot regenerate the nucleus. 
We now see that the regeneration of organs lost in 
consequence of the.spontaneous division of cellules, is 
subjected to the same law as the regeneration follow- 
ing upon artificial division; the protoplasm cannot re- 
generate a nuclear element any more in the one case 
than in the other; in order to effect reproduction, 
therefore, this element must divide. 


OF MICRO-ORGANISMS. 105 


IX. 
CONCLUSION. 


THE conclusions relative to psychological phenom- 
ena arrived at in the foregoing treatise, are in contra- 
diction with the opinions generally received upon the 
psychology of the cell. Scientists have held, that cell- 
ular psychology is represented wholly and solely by 
the laws of irritability. In his Zssaz de Psychologie 
Générale, a work in so many respects remarkable, M. 
Richet has assumed the advocacy of this view; the 
correctness of which we have no hesitation in disput- 
ing. In the work just mentioned, the distinguished 
professor has written the following: 

“There exist simple beings which appear to be 
nothing more than a homogeneous assemblage of irri- 
table cellules. Motory reaction, consequent upon 
irritation’ from without, constitutes their life of rela- 
tion. Irritability is their life complete, but this, in 
effect, is psychic life; so that cellular irritability can 
be considered the same as elementary psychic life.” 

From an attentive perusal of this passage it will 
be seen that M. Richet brings within the category of 
irritability, not only unicellular organisms, but also 
pluricellular organisms formed by the union of homo- 
geneous cellules. 

M. Romanes, in his work upon Mental Evolution, 
without coming to a conclusion so definite as M. 
Richet, seems to us to have reduced the psychic ac- 
tivity of proto-organisms to within very narrow limits. 
We are impressed with the fact upon glancing over . 
his Diagram of Mental Evolution: he recognizes 
nothing but excitability, for example, in the ovule and 
spermatozoid of man. This is manifestly erroneous. 


106 THE PSY CHICRELLE 


The sexual elements, and especially the spermatozoid, 
of all unicellular organisms are certainly the ones which 
show the most highly developed psychical functions: 
the act of seeking and approaching the ovule, which 
is frequently situated at quite some distance from 
where the male element is deposited; the length of 
road to:be traveled; the obstacles to be overcome; 
all point to faculties in the spermatozoid that are not 
explainable by simple irritability. : 

Hitherto, apparently, writers who have essayed to 
present the psychology of micro-organisms, have con- 
tented themselves with schematic notions instead of 
basing their theories upon the direct observation of 
these interesting creatures. By the aid of exact data, 
we have shown that in both vegetable and animal 
micro-organisms phenomena are encountered which 
pertain to a highly complex psychology, and which 
appear quite out of proportion to the minute mass 
that serves them as a substratum. 

We shall first of all advert to the term irritability, — 
which, though long in use, has not in our opinion been 
happily chosen; since it is in the highest degree ambig- 
uous, and not suggestive of an exact signification. — 
We might call to mind in this connection, the reflec- 
tion made by Kant upon obscure properties, which he 
compares to easy-chairs upon which the mind unbends 
itself and rests. In place of discussing words, let us 
endeavor to discuss facts. 

What are we to understand by irritability? We 
may give the expression a very broad or a very re- 
stricted meaning. We may makeit express the prop- 
erty which every organism possesses, of reacting 
upon excitation. In this general sense we may say 
that irritability includes within itself all of psychology, 


OF MICRO-ORGANISMS. 107 


the most highly developed, as well as the most ele- 
mentary; for upon ultimate analysis every psychical 
manifestation consists in a response to an excitation. 

Evidently, it is not in this: general and somewhat 
common sense that M. Richet has intended to employ 
the word. For a more exact definition, let us consult 
his work, of which, a whole chapter, the first, is de- 
voted to this subject; the author enumerates and de- 
velops at length the laws of irritability: 

' 1. Every action that modifies the actual condition 
of a cell is an irritant of that cell. 

. 2. Every external force, provided it has a certain 
intensity, is capable of inducing cellular irritability. 

3. The movement in response to irritation is pro- 
’ portional to the excitation. 

4. The movement in response to irritation is, for 
equal irritations, stronger in proportion as the equilib- 
rium of the cell is less stable; in other words, stronger 
in proportion as the cell is more excitable. 

5. The response to the irritation, is a movement in 
the form of a wave, which has a very short latent pe- 
riod, a period of ascent, correspondingly brief, and a 
very long period of descent. 

6. The movement of the cell upon irritation is, for 
equal irritations, stronger in proportion as the irrita- 
tion has been more sudden. 

7. The movement in response to a brief irritation 
lasts much longer than the irritation has lasted. 

8. Forces which, alone, appear impotent, become 
effective when repeated; for they have, in spite of 
their apparent inefficacy, increased the excitability of 
the organism. 

The statement of these various laws, gives the term 
irritability a precision which it lacked. M. Richet had 


108 LE PSYCHIC LILLE 


in view particularly the muscular fibres, and the laws 
of irritability are only supposed to cover a series of 
physiological experiments made upon the reaction of 
a striated muscle. They are not, then, hypothetical 
laws, but are much rather particular experiments gen- 
eralized and extended to undifferentiated protoplasm. 
It is proper to remark here, that we have not as yet — 
been able, by means of direct experiments, to ascer- 
tain from life the laws of irritability in undifferentiated 
protoplasm. The experiments made upon this point,— 
for instance, the experiment causing the protoplasm 
of a detached cell to contract by means of an electric 
current,—have not yet been brought toa precise result; 
for the structure of protoplasm is so delicate and so 
complex, that even the slightest excitation suffices to 
produce an alteration, and since it is difficult to distin- 
guish the contraction of the protoplasm from its coag- 
ulation. But we shall pass by this subordinate ques- 
tion. 

The question now remains, whether the compli- 
cated experiments made in muscular physiology, which 
M. Richet generalizes and extends to the physiology 
of all cellules, include and comprehend the whole psy- 
chology of an independent organism, and whether we 
may say with M. Richet, that irritability (thus under- 
stood) represents all of cellular psychology. 

Plainly not. The numerous facts which we have 
cited in the foregoing essay, transcend the too narrow 
limits within which it has been attempted to confine 
the psychology of the cell. We shall restrict our- 
selves to the mention of one of these phenomena, to 
show the complexity of the psychic life of micro-organ- 
isms: it is the existence of a power of selection, exer- 
cised either in the search for food, or in the manceu- 


OF MICRO-ORGANISMS 10g 


vres attending conjugation. This act of selection is a 
capital phenomenon; we may take it as the character- 
istic feature of functions pertaining to the nervous 
system. As Romanes has indeed observed, the power 
of choice may be regarded as the criterion of psy- 
chical faculties. Going farther, we might be able to 
say that selection comprehends the properties of the 
nervous cellule, as irritability comprehends the prop- 
erties of the muscular cellule. 

Scientists have endeavored to explain the mechan- 
ism of this choice. They have pretended to solve it 
by saying that it was dependent upon the relation be- 
_ tween the chemical composition of the cellule making 
the choice and the chemical composition of the body : 
selected. ; 

Such explanations are purely verbal. Undoubt- 
edly, the faculty of selection, of which protoplasm 
seems to be possessed, is founded in the character 
of its chemical composition. Chemistry lies at the 
basis of physiology, but chemistry does not explain 
physiology, and it is quite evident that that property . 
which protoplasm possesses of making a choice be- 
tween several excitations, is a physiological property. 

However that may be, we may resume all the fore- 
going into the statement that every micro-organism 
has a psychic life, the complexity of which transcends 
the limits of cellular irritability, from the fact that 
every micro-organism possesses a faculty of selection; 
it chooses its food, as it likewise chooses the animal 
with which it copulates. 

M. Richet has defended his opinion in opposition 
to the one I have pronounded, in a note published in 
the Revue Philosophique for Febuary 1888, wherein he 
speaks as follows: 


IIO THE PSYCHIC TARE 


At the beginning of his essay upon the Psychic Life of Micro- 
Organisms (Revue Philosophique), M. Binet expresses himself as 
follows: ‘‘In the lower beings that represent the simplest forms of 
life, we find manifestations of an intelligence which greatly trans- 
cends the phenomena of cellular irritability. Thus even on the 
very lowest rounds of the ladder of life, psychic manifestations are 
very much more complex than is usually believed, and the concep- 
tion of cellular psychology which some very recent authors have 
formed, seems to me a very crude analysis of the most delicate of 
phenomena.” 

AsI have upheldin my Zssaz de Psychologie Généra/e,and in some 
measure—however little—developed this admitedly old idea, that 
cellular irritability is the beginning of psychical activity, I request 
the permission to speak in defence of an opinion so roughly han- 
dled by M. Binet. 

Now, it appears to me that M. Binet has allowed himself to 
become involved in illusion respecting the word cellule. A cell, in 
the eyes of the embryologist and the morphologist, has a well-de- 
fined meaning. But M. Binet does not seem to have comprehended 
the fact, that for the physiologist and the psychologist, the essen- 
tial condition of cellular unity is homogeneity. It is possible that 
the infusoria, the strange story of whose life M. Binet relates to 
us, are single-celled organisms. I am in no wise qualified to decide 
as to this; but whether a single cell, or a group of cells, it matters 
little, in my opinion, provided the single cell is differentiated to 
the same degree that it would be if composed of several cells not 
homogeneous. 

I appeal to M. Binet himself and to the cuts of his essay. When 
he shows us an “zug/lena with eyes, esophagus, mouth, contractile 
vesicle, contractile reservoir (fig. 6); when he carefully describes 
the shape of the flagellum, the nettle-like tentacles, the tongue- 
shaped organs, the ocular spots, the trichocysts, and the peristome; 
when he assumes special vervous centres endowed with various at- 
tributes (p. 22): he cannot induce us to admit that the psychology 
of these complicated organisms is the same as the psychology of 
the simple cell. I repeat, it is quite immaterial to me that people 
affirm by the authority of embryology that this or that is a single 
cell. If that cellule have ocular organs, a nervous system, a mouth, 
an esophagus, and a heart, I shall, despite any and every hypoth- 
esis of the embryologists, refuse to regard it as being physiologi- 
cally a homogeneous cell, as is, for example, a muscular fibre. 


OF MICRO-ORGANISMS. TBI 


The size will not affect the matter at all. The same desires, 
says Montaigne, stir mite and elephant alike. The psychic life of 
the bee is as complex as that of the whale, and if a microscopic in- 
fusory possess eyes, mouth, prickles, and heart, it evidently pos- 
sesses them in order that itmay make useof them, and accordingly 
I shall treat it as a complex organism upon the same ground that I 
do a snail or a grasshopper. Embryology will not force me to the 
extremity of regarding such a creature as a simple organism be- 
cause it is derived from a single cell. 

In my opinion, therefore, it is that unfortunate word ztce//u- 
far, that has made M. Binet believe that, Infusoria being unicel- 
lular organisms, the elementary psychology of the cellule applied 
to them. M. Binet has allowed himself to be deceived by a word— 
a thing that often happens in matters of science. For my own 
part, in order to avoid any confusion, I would like to say that the 
elementary psychology of the cellule ought not by rights to be ap- 
plied to anything except to homogeneous cellules; for the psychol- 

ogy that has to do with complex cells—real organisms with organs 
and apparatus of their own—must certainly be as complex as the 
psychology of animals wholly differentiated. 

The laws of irritability act in all their simplicity and rigor 
among simple beings. In fact, in every instance of investigation 
into the nature of simple organisms, or such as appear simple by 
the optical instruments at our disposal (a fact that does not always 
Tigorously prove their simplicity), as bacteria, for example,—we 
find that chemical irritability is the apparently sole law of move- 
ment. What else, indeed, are the movements of those bacteria so 
thoroughly studied by M. Engelmann, if not an affinity for oxygen, 
in other words the simplest and most universal chemical phenom- 
enon in all nature? 

And so the critigue of M. Binet will not stand. On the con- 
trary, it seems to be well established that complex organisms, 
whether single-celled or many-celled, have a psychology corre- 
sponding in complexity to the degree of differentiation their organs 
have attained, while simple beings—and they are simple only if 
homogeneous—have a simple psychology which is probably con- 
tained in the laws of Irritability only. Cu. RICHET. 


My reply to the letter of M. Richet, published in 
the same number of the Revue Philosophigue, may be 
offered as a general conclusion to my work. With the 


BIg LHE PSYCHIC LIRT 


omission of all polemical features, it is in substance 
as follows: 


In giving the psychology of these microscopic creatures the 
name of cellular psychology, I have not invented a new term, nor 
given a new sense to an old one. Quite some time before me, M. 
Heckel had made a study of cellular psychology and his investiga- 
tions, like my own, were based entirely upon the observation of 
animal and vegetable micro-organisms. Furthermore, micro-or- 
ganisms being represented by a single cellule (and this doctrine is 
now universally accepted), the study of their psychical manifesta- 
tions can, in my opinion, with perfect propriety be styled cellular 
psychology. 

M. Richet takes exception to the use of the latter expression; 
but he does so while substituting for the old definition of the word . 
cell, one quite his own. To him, a micro-organism like the Eu- 
glena, which has an eye, a mouth, an esophagus, and a contractile 
vesicle, would not beacellule. To admit the latter view, means, 
in his own words, to become involved in illusion respecting the 
word cellule. In our judgment, the question here is by no means 
one of optical illusion, but one of verbal definition. What, ac- 
cordingly, is a cellule? ‘‘ For the physiologist and psychologist,” 
says M. Richet, ‘‘ the cellule has not a distinct entity, or, at least, 
that entity, that unity, lacks an essential condition, namely, homo- 
geneity.” 

To M. Richet, the cellule is a homogeneous body; a body that 
comprises differentiated parts is not a cellule. ~ 

It is unnecessary to remark upon how far the latter concep- 
tion of a cellule diverges from the usual and commonly accepted | 
definition of the word. Hitherto, scientists have understood by 
the term cellule, a body made up of the union of two essential 
parts, a quantity of protoplasm and a nucleus. The scientific world 
argues as to whether elementary forms exist which do not contain 
a nucleusand which should be termed cyfodes, as proposed by M. 
Heckel. The careful observation of micro-organisms by means of 
perfected technical processes has enabled us to discover hundreds. 
of nuclei in the very cellules which M. Haeckel classed among the 
cytodes. Such is notably the case with many algz and lower-class 
fungi. The Moners—a group of micro-organisms believed to have 
no nucleus—grow numerically less and less, in proportion as they 
are more carefully studied. It is true, we are now no more able 


OF MICRO-ORGANISMS. — 113 


than formerly, to show the presence of a nucleus in bacteria; but 
that does not prove that the bacteria have none. Our knowledge 
of the morphology of microscopic organisms is wholly relative, 
and depends upon the degree of perfection attained by technical 
science. _When we bear in mind that the presence of a nucleus re- 
mained for a long time unobserved in organisms several hundred 
times larger than the bacteria, we ought not to besurprised at hav- 
ing been unable to discover one in these smaller creatures. 


We may even go further, and question the material existence of 
a body formed solely of protoplasm, basing our opinion upon the ex- 
_ periments of Gruber, Nussbaum, and Balbiani, as reported in my 
article, and upon the more recent observations of Klebs which are 
in perfect agreement with the results of the investigators just cited. 
All have shown that the nucleus is an element essential to the life 
of the cellule, and that, when a fragment of a cellular body strip- 
ped of a nucleus is procured by artificial section, this fragment does 
not reproduce the organs it lost by being severed; it does not heal 
its wound, it does not refashion its form, and, what is more, at the 
end of a certain time its protoplasm, being withdrawn from the in- 
fluence of the nucleus, suffers complete disorganization. These 
experiments were made not only upon animal micro-organisms, but 
upon vegetable cells also. They prove the primordial importance 
of the nucleus in the cellule and thereby render doubtful the exis- 
tence of cellules deprived of a nucleus. 


Since every cellule contains, in all likelihood, two distinct dif- 
ferentiated elements, the protoplasm and the nucleus, which have 
neither the same physical structure, nor the same chemical nature, 
nor the same physiological functions, we may understand that it 
would be exceedingly difficult to name a single instance of a 
simple homogeneous cellule. It is the proper place to add that 
neither protoplasm nor nucleus, each regarded by itself, are homo- 
geneous substances. . It is unnecessary to enumerate all the investi- 
gations that have been made upon this point. Let us call to mind 
merely the fact that from the morphological point of view proto- 
plasm appears to be composed of two substances, a homogeneous 
semi-liquid substance and a firmer substance exhibiting, as auth- 
orities upon the subject say, sometimes the form of detached fila- 
ments and at others a structure of a reticulate character. 


At the present day, accordingly, it is impossible to allow that 
homogeneous cellules exist, without falling back to Dujardin’s 


114 THE PSYCHIC LIFE 


theory of the sarcode. There are really no simple organisms, 
and such as appear so are merely imperfectly known. 

However, it will not do perhaps to take literally the terms em- 
ployed by M. Richet. When he speaks of homogeneous cellules it 
is possible that he wishes to speak merely of cellules in which, aside 
from the nucleus, no other differentiated organ is to be found. 

Now, it is quite important to note that, even of organisms 
made up simply of protoplasm and nucleus, the psychology is ex- 
tremely complicated, and is not contained exclusively in the laws 
of irritability. 

The Vampyrella Spirogyre, classed by Zopf among the animal- 
fungi, and the place of which is still so little known, is a being the 
body of which is composed of protoplasm and nucleus simply. 
So far no other differentiated organ has been found in thiscreature, 
except from one to four contractile vesicles. Employing the ter- 
minology of M. Richet, perhaps we ought to call this being a sim- 
ple cellule; yet this simple cellule has quite a complicated psy- 
chology: it exercises choice in the selection of its food, attacking 
Spirogyra only. : 

The same is the case with the M/onas amyli, which, having 
neither eye nor mouth, represents to M. Richet a simple cellule; 
still, the J/onas amyli exercises choice in selecting its food, as it 
feeds exclusively on grains of starch. 

The structural elements of the tissues do not differ from the 
micro-organisms whose psychological history I have endeavored to 
unfold, so much as might be imagined: they show the same powers 
of selection, and on this point I shall only instance the epithelial cel- , 
lules of the intestines or the phagocyte cellules, the attributes of 
which I have described in my essay, and which are able to dis- 
criminate, for instance, between bits of fat and particles of coal, 
absorbing the former and leaving the latter. 

I repeat it, therefore, no living cellule, strictly so defined, is a 
simple cellule, and Ido not think that M. Richet has advanced a fit- 
ting illustration in mentioning the muscular cell, for the latter is 
one of the most highly differentiated that there are. 

I cannot imagine, accordingly, to what elements, to what be- 
ings clearly defined, we could apply the simple-cellular psychology 
reduced to mere irritability, that M. Richet asks me to distinguish 
from the complex-cellular psychology, which would be exclusively 
reserved for the animal and vegetable micro-organisms that I have 
described. 


OF MICRO-ORGANISMS. PUL 


It appears to me that this simple-cellular psychology lacks a 
foundation; it is a conception of the mind, rather than a study 
based upon observed facts. 

In M. Richet’s book I find no indication as to what sort of be- 
ings he means to distinguish thereby. He contents himself (pp. 20 
and 27) with speaking of simple beings without otherwise defining 
them. ‘Towards the close of his remarks upon my work, M. Richet 
cites an instance of simple beings, viz., the bacteria; in his judg- 
ment, chemical irritability appears to be the sole law conditioning 
their movements. What are the movements of the bacteria, he 
asks, if not an affinity for oxygen; in other words, the simplest and 
most universal chemical phenomenon that exists in all nature? 

In our judgment the latter phrase is to be taken metaphorically. 
We believe that as yet no one has demonstrated that the move- 
ments of a living being, in moving towards a distant object, how- 
ever simple they may be, can be explained merely by a chemical 
affinity acting between that being and that object. It is certainly 
not chemical affinity that is acting, but much rather a physiological 
need. 

Psychic life, like its substratum, living matter, is, when closely 
studied, an exceedingly complex subject. This fact is, with me, 
a profound conviction; it rests, not upon abstract ideas and 
methods, but upon the observations that I have given, observa- 
tions that are not founded upon my own personal authority alone, 
but which are drawn from the highest authorities, and most of 
which I have been able to verify with my own eyes. 


ALFRED BINET. 





a THE PSYCHIC LIFE. 


APPENDIX. ell 
The subjoined cuts, explanatory of the conjugation 
of Micro-organisms, refer respectively to the descrip- 
tions on pages 67, 67 and 68, 68, 69 and 70, 71 and 72. 





Fig. 7 2.—Positions preliminary to 
conjugation among the faramectum 
aurelza, (Balbiani.) 





Fig. 7 4.—Several pairs of Stentor Fig. 7¢. Position preliminary to 
ceruleus fixed upon a conferva fila- the copulation of the Stylonychia 
ment, enlarged fifteen diameters mytilus, The two animals are super- 
(after Balbiani). imposed upon each other by their 


ventral faces (Balbiani), 


OF MICRO-ORGANISMS. 117 





Fig. 7 d2.—Gemmiform conjugation of the Vorticellinze (Carchestun poly- 
pinum). <A, first stage: the microgonidium zz has fastened itself by a filament 
upon the peduncle of the macrogonidium. #8, amore advanced stage: the mi- 
crogonidium has fastened itself directly upon the body of the macrogonidium, 
and its substance begins to penetrate into the latter. In both individuals the 
nucleus has separated into small rounded fragments, and in the microgonidium 
are seen the two striated segments resulting from the division of its nucleolus. 
C, last stage of the conjugation. The microgonidium, completely void of its 
contents, remains attached to the body of the macrogonidium under the form 
of a minute hollow tube, which in the end drops away,—77a, macrogonidium; 
mz, microgonidium; z, nucleus; zz, nucleolus; v. c., contractile vesicle. (Figures 
from M. Balbiani.) 


118 











Fig. 7 e.—Conjugation of the Chilodon cucuillulus. 


wi 
1 pale 
iani.) 


UC, 
ew nucleolus zuz. (Figures from M. Balbi 


gns of re- 
, of which one 


; mu, nucleolus 


gins to show si 


r together 
gment not exchanged, to forma 


qual sizes; the larger, 27 


£, the old nucleus, z, reduced to a smal 


egments, brought nea 


f conjugation; 4, mouth; ~, nucleus 
ll fuse with the se 


ation, 722, 


, hear by which is seen then 


inning o 


us into two segments, zz’, zu’; the nucleus z be 


A, beg 
of the new form 


jugation contains two nucleolar s 
8 


y course of exchange, and wi 


B, division of the nucleol 
opposite b 
D, division of the se 


, the smaller, the nucleolus 


is replaced by the new nucleus zz 


gment (Maupas). 


C, each of the two individuals in con 
new nucleus 


probably comes from the individual o 


multiple contractile vesicles. 
gression. 

compound se 

become the 

and rumpled mass, 


LLL PS VCH Cet Licks 


EXPLANATION OF FIG. 7 E. 


In the Chilodon cu- 
cullulus the following is 
the series of phenomena 
presented (the row of fig- 
ures given opposite, have 
been procured through 
the kindness of M. Bal- 
biani, and will serve to il- 
lustrate our description): 
The figure A shows the 
beginning of conjugation; 
each animal isshown with 
its mouth (4), its multiple 
contractile vesicles (v. ¢.), 
its nucleus (7), and its nu- 
cleolus (zz); the nucteo-. 
lus will become the main 
seat of the modifications 
effected in fecundation. 
In the figure Z the prin- 
cipal change pertains to” 
the nucleolus; in each of 
the two animals, the nu- 
cleolus has moved away 
from the nucleus and has 
begun to break apart into 
two segments; the nucleus 
commences to show signs 
of regression. Between 
the figure Zand the figure 
C phenomena take place 
of the highest importance, 
but which are still the 
subject of dispute. The 
following appears from 
present investigations to 
be the most probable: the 
two animals in conjuga- 
tion exchange with each 


~ 


OF MICRO-ORGANISMS. 11g 


other one of the capsules produced by the division of the nucleolus, 
so that when we come to the phase of the process represented in 
figure C, we find an animal which contains, besides its nucleus, two 
nucleolar segments in immediate proximity (w’ mu’); it was the 
same in figure 4, each animal already possessed two nucleolar seg- 
ments, but these segments were obtained from the division of the 
nucleolus properly belonging to the animal itself, while in figure C, 
in consequence of an exchange effected, one of the nucleolar seg- 
ments belongs.originally to each animal and the other comes from 
its mate. 


M. Balbiani, who made the first observations upon these phe- 
nomena of a nature so delicate and complex, originally supposed 
that the two adjacent nucleolar segments, which have been rep- 
resented in the figure C, were produced by the longitudinal di- 
vision of the nucleolus exchanged between the two animals in con- 
jugation. 

M. Maupas has recently proposed a different explanation, 
which seems to be further corroborated by the very figure given 
twenty years previously by M. Balbiani. According to M. 
Maupas the segment exchanged proceeds to fuse with the segment 
not exchanged, in order to form a compound segment; the two con- 
tiguous segments, seen in figure C, would not, therefore, be the re- 
sult of the division of one segment solely, but the first stage of the 
conjugation of two elements having different origins. A fact which 
apparently argues in favor of this opinion, is the aspect presented 
by the two segments; if they proceed from a division, we would 
find there certain phenomena of caryokinesis, which were further- 
more completely unknown at the time when M. Balbiani made his 
first observations. 


However this may be, it is seen by figure C that the regression 
of the old nucleus (7) is sharply marked. 

In the figure D, the two nucleolar segments have fused to- 
gether and have formed a compound segment, which segmentates in 
its own turn; the two new products of that segmentation grow to 
unequal sizes; the largest capsule attains a size of forty thou- 
sandths of a mm.; it is this that forms the new nucleus of the 
Chilodon. The second capsule shrinks and becomes compressed, 
it takes its place beside the first one and becomes the new nucleolus. 

The figure Z represents the last stage of the phenomenon; the 
animal is in possession of its new nucleus and its new nucleolus; 


120 LITE PSV CTH G LGPL 


the old nucleus is reduced to a small pale and rumpled mass and 
will shortly disappear. 

To recapitulate, then, if the opinion of M. Maupas (who did 
not study this species, but like ones) be accepted, the nucleolus di- 
vides into two capsules: the one, playing the part of a male ele- 
ment, is exchanged between the two animals in conjugation, and 
proceeds to fuse with one of the capsules derived from the division . 
of the nucleolus of the other animal; the other capsule, which acts 
the part of a female element fuses in the same way with the male 
element coming from the other animal. ‘The result of that fusion 
is a compound capsule which, undergoing a process of division, pro- 
duces the new nucleus and the new nucleolus of the animal fecun- 
dated. 


ADDENDA. 


Notes, References, Authorities, etc., omitted in the text: 

Page 1, line 16. The doctrine of unicellularity in regard to the 
Infusoria has been upheld by Sibold and Kolliker; the ma- 
jority of naturalists have conceded it. 

Page g, line 21, et seq., vide Pfliiger’s Arch., Vol. XXIII, 1880. 

Page 10, line 4, vide Rouget, Revue Scientifique. March 15, 1884. 

Page ro, line 13, vide Annales des Sciences Naturelles, 1835, Vol. IV, 
pp. 348 and 261. ; 

Page 12, line 29, et seq., vide Ardeiten aus dem zodlog. Institut in 
Wiirzburg, herausgegeben von Prof. C. Semper, Vol. I. p. 
9, 1872. 

Page 15, lines 12 and 13, vide Morphologisches Fahrbuch, Vol. X. 
1885, Pp. 534- 

Page 16, line 25, vide Pfliiger’s Arch., 1876. 

Page 19, line 28, vide Balbiani, Lecons sur les Sporozoaires. 

Page 20, line 6. By protoplasm’ in this connection is understood 
the entire cellular body; the distinction of function between 
the protoplasm properly so called, and the nucleus, is estab- 
lished later on in the essay. 

Page 26, lines 9 and 10, vide Comptes rendus de l’ Acad. des Sciences, 
Nov. 2, 1886, No. 18. . 

Page 29, line 26, vide Bot, Zeitung, 1881, 1883, 1884, 1886. 

Page 46, last line, vide E. Maupas, Etude des Infusoires ciliés, 
Arch, de zo0l. expér., 1883, No. 4. 

Page 58, lines 30 and 31, vide Henneguy, Sur la reproduction du 
Volvox divigue, Acad. des Sciences, July 24, 1876. 








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Laid paper. Veg. parch. binding. Gilttop. 96 pages. Price, 75 cents. 


EPITOMES OF-THREE SCIENCES. 


. COMPARATIVE PHILOLOGY; Tue Stupy or SANnskrirT. 
By Prof. H. Oldenberg, of the Univ ersity of Kiel, 


2. EXPERIMENTAL PSYCHOLOGY. 
By Prof. Foseph Fastrow, of the University of Wisconsin. 


3. OLD TESTAMENT HISTORY; or, THE RISE OF THE PEOPLE OF 
ISRAEL. 

By Prof. C. H. Cornill, of the University of Kénigsberg, with especial 

introductions by Professors Oldenberg and Cornill and prefatory re- 

marks by the Editor of 7ke Open Court. 140 pages. Cloth, 75 cents. 


EY OPEN PCOURT SEEDS FING CG. 


770 MONON BUILDING, 324 DEARBORN STREET, CHICAGO 


The Religion of Science Library. 





A collection of bi-monthly reprints of books and articles here- 
tofore published in The Open Court. Yearly, $1.50; single num- 
bers, 25 cents. The books will be printed upon good paper, from 
large type. 


The following have already appeared in the series: — 


1. July, 1893. Zhe Religion of Sctence. By PauL Carus. 
2. Sept., 1893. Z7hree Introductory Lectures on the Science of 
Thought. By F. Max MULLER. 


3. Nov., 1893. 7Zhree Lectures on the Science of Language. By 
F. Max MULLER. 


Jan., 1894. The Diseases of Personality, By Tu. Risor. 
Mar., 1894. Zhe Psychology of Attention. By Tu. RIpor. 





The following are in preparation : 

The Diseases of the Will, By Tu. Rigor. 

The Lost Manuscript. A Novel. By Gustav FREYTAG. 

The Study of Sanskrit. By Pror. H.-OLDENBERG. 

Old Testament History, By Pror. C..H. C_RNILL. 

The Ethical Problem. By Pau Carus. 

The Origin of Language, and The Origin of. Reason. By Lupwic 
NOIRE. 

Memory as a General Function of Organised Matter, and The Spe- 
cific Energies of the Nervous System, etc. By Pror. Ewarp 
HERING. 

On Double Consciousness, and The Psychic Life of Micro-Organ- 
esms. By ALFRED BINET. 

fundamental Problems, and other works. By Pau Carus. 





THE OPEN COURT PUBLISHING CO., 


770 MONON BUILDING, 


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